Actions

Planetary protection for a Mars sample return

From Astrobiology

One of the early proposals for a Mars Receiving Facility - the LAS version with extensive use of robotic handlers for the samples

There are several proposals for a Mars sample return mission (MSR) to bring back to Earth rock and dust samples from Mars to study. It is currently unknown whether or not life forms exist on Mars. If such life exists, a MSR could potentially transfer viable organisms resulting in a risk of back contamination — the introduction of extraterrestrial organisms into Earth's biosphere.

The NRC and ESF studies concluded that, though the potential for large-scale negative effects appears to be very low, it is not demonstrably zero,[1] and that the samples should be treated as biohazardous to the environment of Earth until shown to be safe.

Most participants are agreed that a MSR should be carried out eventually. There is however considerable diversity of views on the details of how a MSR should be conducted, both for reasons of contamination and science value. This is the subject of this article.

The NRC and ESF findings on risks of environmental disruption are accepted by most participants in this debate (with the notable exception of Robert Zubrin[2][3]). As a result, it is agreed by most researchers that a full and open public debate of the back contamination issues is needed at an international level.[4] This is also a legal requirement.[5][6]

Contents

Plans to return a sample to Earth before detailed examination[edit | hide all | hide | edit source]

A Mars Sample Return (MSR) to the Earth surface has been considered many times since the first proposal in 1979,[7] due to the high science value expected for carefully selected samples from Mars examined with the full range of facilities we have available on Earth.

NASA's Mars 2020 rover will cache samples which they hope to return direct to Earth in the 2020s, possibly as soon as 2026.

There have been many previous plans by NASA in the Mars Next Generation program.[8][9] China also has considered a plan to return a sample by 2030.[10]

Samples returned under these proposals would be examined for biosignatures on Mars first, but the proposals suggested so far for a MSR to Earth do not include any plans for detailed examination on the Mars surface, such as with Scanning Electron Microscopes, DNA sequencers, or labelled culture experiments. Also the plans proposed so far do not include tests for biohazard potential in Earth-like environments prior to return to Earth. All these tests would instead be carried out on Earth after the sample return mission.[11]

As a result, these plans depend on adequate containment of the samples during the return journey and in the receiving facility on Earth until the tests can be completed on Earth.[11]

View presented in the NRC and ESF study group reports and Planetary Protection Office summaries[edit | hide | edit source]

The view in the reports from the National Research Council[12] and the European Space Foundation,[13][14] as well as the Planetary Protection office[15] is as follows:

The risks of environmental disruption resulting from the inadvertent contamination of Earth with putative martian microbes are still considered to be low. But since the risk cannot be demonstrated to be zero, due care and caution must be exercised in handling any martian materials returned to Earth.[16]

To deal with these issues, the NASA Office of Planetary Protection[17] recommends construction of a special a Mars Receiving Facility. They recommend that the facility should be operational at least two years prior to launch,[18] with various estimates on the time taken to build the facility and bring it to operational readiness. Preliminary studies have warned that it may take as many as 7 to 10 years to get it operational.[19]

The official reports stress the need for public debate at the international level due to the ethical issues involved.

RECOMMENDATION 10:

Considering the global nature of the issue, consequences resulting from an unintended release could be borne by a larger set of countries than those involved in the programme. It is recommended that mechanisms dedicated to ethical and social issues of the risks and benefits raised by an MSR are set up at the international level and are open to representatives of all countries.[20]

The aim of this article is to present in detail some of the varying viewpoints on the back contamination risks and the science benefits of a Mars sample return, including minority views held by only one scientist or ethicist. These are all relevant to the international debate that will be required before a Mars Sample Return.

Concerns and issues raised[edit | hide | edit source]

First a brief overview of the issues.

  • Some researchers [21][22][23][24] are mainly concerned about issues of back contamination of Earth by accidentally released Martian micro-organisms.
  • Others are concerned about the high cost of a MSR on the basis that it will be some time before we know enough about Mars to select suitable samples to examine on Earth, and until then, run a high risk of returning bioligically uninteresting samples.[25][26]
  • Others are concerned that any samples would be contaminated by Earth life during the return journey, so reducing their value for scientific research.[27]

These issues of back contamination of Earth, selection of interesting samples on Mars, and sample contamination by Earth micro-organisms, are also raised in the official reports as well. It is generally agreed by almost all researchers that these are issues that need to be addressed in any plans for a MSR.

Back contamination concerns for a Mars sample return[edit | hide | edit source]

These concerns were originally raised by Carl Sagan in 1973 in his book the Cosmic Connection,[21] and Carl Woese.,[22] and later by Lederberg [24]

Carl Woese, who first classified the Archaea, the third domain of life[28] said in an interview:

When the entire biosphere hangs in the balance, it is adventuristic to the extreme to bring Martian life here. Sure, there is a chance it would do no harm; but that is not the point. Unless you can rule out the chance that it might do harm, you should not embark on such a course.[22]

Carl Sagan wrote in his book Cosmic Connection:

...The likelihood that such pathogens exist is probably small, but we cannot take even a small risk with a billion lives.[21]

These concerns centre on the biohazard potential of martian lifeforms

Biohazard potential of martian life[edit | hide | edit source]

The potential of Martian life to create a biohazard on Earth was first raised by Carl Sagan in 1973 in his book "Cosmic Connection".[21] The concern has been reviewed many times since then with the same or similar conclusions.

Sagan wrote:

Precisely because Mars is an environment of great potential biological interest, it is possible that on Mars there are pathogens, organisms which, if transported to the terrestrial environment, might do enormous biological damage - a Martian plague, the twist in the plot of H. G. Wells' War of the Worlds, but in reverse. This is an extremely grave point. On the one hand, we can argue that Martian organisms cannot cause any serious problems to terrestrial organisms, because there has been no biological contact for 4.5 billion years between Martian and terrestrial organisms. On the other hand, we can argue equally well that terrestrial organisms have evolved no defenses against potential Martian pathogens, precisely because there has been no such contact for 4.5 billion years. The chance of such an infection may be very small, but the hazards, if it occurs, are certainly very high...[21]

The microbiologist Joshua Lederberg made a similar point

Whether a microorganism from Mars exists and could attack us is more conjectural. If so, it might be a zoonosis to beat all others.

On the one hand, how could microbes from Mars be pathogenic for hosts on Earth when so many subtle adaptations are needed for any new organisms to come into a host and cause disease? On the other hand, microorganisms make little besides proteins and carbohydrates, and the human or other mammalian immune systems typically respond to peptides or carbohydrates produced by invading pathogens. Thus, although the hypothetical parasite from Mars is not adapted to live in a host from Earth, our immune systems are not equipped to cope with totally alien parasites: a conceptual impasse.[24]

These early concerns have been repeated in the detailed assessments by later study groups.

National Research Council review of biohazard potential of returned samples[edit | hide | edit source]

The National Research Council review was undertaken in 2009 (and previously in 1997) and published as their "Assessment of Planetary Protection Requirements for Mars Sample Return Missions".[29] They confirm the earlier concerns as still a matter that needs attention.

This report is the basis for the later 2010 ESF report which is in agreement with its conclusions about the biohazard potential of any mars sample return.

They reviewed the then current research on relevant subjects, to come to their conclusion.

  • Potential for habitable conditions on Mars. They concluded that research since the last report has enhanced the prospect that habitable environments were once widespread on Mars, and has improved understanding of the potential for modern habitable environments, and "enhanced the possibility that living samples could be present in samples returned from Mars".[20][30]
  • Capability of micro-organisms to survive on Mars. To assess this, they reviewed recent research in microbial ecology in Chapter 3. They noted the discovery of new extremophiles in an increasing range of habitats, including highly acidic locations, conditions of extreme cold, of ephemeral habitability, and the capability of some micro-organisms to survive in dormant states for at least 250 million years. They noted the discovery of new organisms and ecological interactions.[31] They also noted the discovery of novel single-species ecosystems such as the one inhabited solely by the chemoautotrophic Candidatus Desulforudis audaxviator. Their conclusion was that these researches highlighted the potential of micro-organisms adapted to live in the Martian environment.[32]
  • Biohazard potential of any martian micro-organisms. They noted that extremophiles have not yet been shown to pose significant biological risk to humans. However in chapter 5, they note that there are comparative studies of extremophiles and of human pathogens "suggesting that evolutionary distances between nonpathogenic and pathogenic organisms can be quite small in some instances." As a result they concluded that the potential risks of biological epidemics can't be reduced to zero.[33]
  • Would the sample include micro-organisms not already delivered to Earth on martian meteorites? To assess this, they estimated that several meteorites a year probably impact Earth from Mars. So the transfer of sufficiently hardy life forms from Mars to Earth via meteorite seems plausible.[34] However, they observed that meteorites in current collections spent from 350,000 to 16 million years in space, and though theoretical models show that shorter transition periods are possible, concluded that the much shorter transit time of a sample return protected in a container could preserve lifeforms that would not survive the passage on a meteorite.[35]
  • Could martian lifeforms transferred to Earth in a meteorite have caused mass extinctions on Earth in the past? Their conclusion was that there is no evidence of this in the recent past but it could not be ruled out as a possibility in the more distant past.

Their overall conclusion was:

The committee found that the potential for large-scale negative effects on Earth's inhabitants or environment by a returned martian life form appears to be low, but is not demonstrably zero.

As with previous reports, the latest 2009 study recommended that the sample be treated as a biohazard until proved otherwise.[36]

ESF update on biohazard risks of MSR[edit | hide | edit source]

The ESF report accepts the general conclusions of the NRC report, but went beyond them in several areas. In particular they made a more detailed assessment of size limits of micro-organisms. Before this study, the accepted size limits [37] were 0.25 µm, derived from a 1999 workshop.[38]

The 2010 ESF study observed that the Mars sample could contain uncultivatable archaea, or ultramicrobacteria. It might contain Martian nanobacteria 0.1 µm if such exist. A recent concern is that it could contain virus-types and genetransfer agents as small as 0.03 µm in size, especially if Mars life and Earth life share a common ancestor at some point.[39] It might also contain forms of life that don't exist on Earth, possibly based on novel life chemistry, which makes it hard to set an absolute lower size.

For the nanobacteria, they accepted recent research that show these 0.1 µm sized cell like objects are mineral deposits, so ruled them out. They discussed ultramicrobacteria and concluded that the smallest free-living self-replicating microorganisms observed are in the range of 0.12–0.2 µm.

They considered viruses, i.e. bacteriophages and viruses of archaea.[40] These they considered unlikely to be of concern if released from containment on their own, separately from their putative martian micro-organism host, because they require specific host adaptations to infect Terrestrial micro-organisms. [41]

They then studied GTAs, which cause cross species transfer of DNA in some species of archaea and bacteria. [42] Here they are referring to research reported in Nature and Science in 2010 (after the NRC report).[43][44] In one striking experiment the researchers left GTAs (conferring antibiotic resistance) and marine bacteria overnight in natural conditions and found that by the next day up to 47% of the bacteria had incoroproated the genetic material from the GTAs : [45]

As a result of reviewing this research, the ESF study group concluded that the risk from virus type and GTA type entities is lower than for self replicating entities and "almost negligible" but still can't be demonstrated to be zero and should be taken account of in their minimum size recommendations.[46]

As a result, they recommended a minimum size of 0.01 µm on the basis that this is nearly half the size of the smallest GTAs known and less than a tenth of the size of the smallest currently known free-living self-replicating microorganisms.

In the case where 0.01 µm can't be achieved at a reasonable cost, and in view of the almost negligible risks from GTAs, they give 0.05 µm as a maximum permitted minimum size. This size was chosen as less than half that of the smallest currently known micro-organisms - so unlikely to contain a free-living microorganism. They recommend that such an increase of the minimum size requirement requires independent review by a panel of experts.[47]

However, in 3.7 Perspectives for the future, they added a caution that it is likely that minimum size limits for viruses and GTAs or free living organisms will reduce further in the future. They thought it unlikely that such a large reduction in size limits will happen again as happened after the 1999 report,[38] though that possibility also can't be completely ruled out. . They recommended that the size limits should be continually reviewed depending on the latest research.[48]

Risk Mitigation for back contamination[edit | hide | edit source]

NASA has addressed back contamination concerns with a proposal to build a special biohazard containment facility to receive the samples, and with a sample return mission designed to break the chain of contact with Mars for the exterior of the sample container[49][50]

In the European Science Foundation study, these risks were studied in more detail and recommendations made to reduce them to levels considered acceptable.

Concerns with integrity of the sample container[edit | hide | edit source]

The 2010 ESF report[49] considers several possible failure modes with the sample container.

  • There is a low risk of an undetected failure to create a seal when the Mars sample is first enclosed in the container. Another risk is that "the sample magazine could be penetrated by a micrometeoroid during transit from Mars, thereby causing exterior contamination and release upon entry".[4][49][51]
  • If any part of the capsule exterior can be contaminated by Mars materials this provides a possibility of contamination of Earth.
  • Also human error, or management decisions could compromise the safety precautions taken for safe sample return.

Risk mitigation for sample container[edit | hide | edit source]

  • Risk of rupture: This risk is reduced by requiring that the capsule is capable of withstanding the shock of impact at terminal velocity.
  • Risk of leaks or micrometeorite penetration: These risks are reduced by using multiple seals and use of methods to detect such leaks if they occur.
  • Risk of exterior contamination This risk is managed by a mission design that ensures that no surface that is exposed to the Mars environment is exposed to Earth. One way of doing this is to send another spacecraft to retrieve the container which receives it within the vacuum of space into a larger sealed container that has never been exposed to Mars and then is sealed and returned to Earth.[52][53]
  • Human error: This risk is reduced by training, redundancy, and making sure critical decisions are not made by tired astronauts.

Issues due to novelty of the proposed Biohazard facilities[edit | hide | edit source]

This describes the issues, see the risk mitigation section for the solutions proposed for these issues.

The ESF report points out that the facility must also double as a clean room, to keep Earth micro-organisms away from the sample. As a result, this greatly adds to the complexity of the facility, and so to the risk of failure, since clean rooms and biohazard rooms have conflicting requirements (biohazard containment facilities are normally built with negative air pressure for instance, to keep organisms in, and clean rooms with positive air pressure to keep organisms out). It will be the first such facility ever to be built.

The ESF report also points out that biohazard facilities are designed to contain known hazards. The new facility must contain unknown hazards as well. It's a much harder problem to contain unknown hazards, especially with the diversity of life forms now known to be potentially hazardous such as GTAs and ultramicrobacteria (as described above).

Other risks mentioned in these studies, and by the Planetary Protection Office include the possibility of human error, accidents, natural disasters, security breach, actions by terrorist or 'activist' groups or crime, leading to release of the materials, once the samples are on the Earth surface.[54]

Target probabilities for proposed biohazard facilities[edit | hide | edit source]

The space studies board study recognised that the risks of release of hazardous particles from a MSR receiving facility can't be reduced to zero. So it is necessary to set a target probability of release that you aim to achieve.

Consequently, risk-mitigation strategies will focus on eliminating the hazard and/or reducing the probability of a negative event. Both will lead to a risk that is considered acceptable, since achieving zero risk is not possible.[55]

One suggestion for an acceptable level of risk was recommended by the ESF-ESSC Study Group

"Based on standards established and adopted at the national and international levels, the ESF-ESSC Study Group recommends that the probability of release of a potentially hazardous Mars particle shall be less than one in a million.".[49]

Risk mitigation for the MSR receiving facilities[edit | hide | edit source]

To deal with the issues of unknown possibly very small forms of life in the sample, the ESF referred to their discussion of size limits (above) and concluded (Recommendation 7) that if possible, the facilities should be designed so that probability should be less than one in a million that a single unsterilised particle of 0.01 µm diameter or greater, if possible, and if that's not possible, that

The release of a single unsterilised particle larger than 0.05 µm is not acceptable under any circumstance[39]

To deal with issues of the novelty of the facilities and of human error, the studies recommended that the receiving facility is operational and the staff trained several years before the Mars samples are brought into Earth's environment. The 2008 report of the IMARS working group report detailed a total of twelve years from initial planning to lander launch.[56] Three architectural firms were approached who provided preliminary plans, the FLAD, IDC and LAS plans, the last of these, the LAS has a fully robotic work force to handle the samples.[57][58][59]

They were not asked to consider human factors and so do not report on ways to mitigate these, except to suggest that care must be taken to minimize human interaction with the sample.[51]

Concerns about incubation period[edit | hide | edit source]

Carl Sagan first raised this concern:

There is also the vexing question of the latency period. If we expose terrestrial organisms to Martian pathogens, how long must we wait before we can be convinced that the pathogen-host relationship is understood? For example, the latency period for leprosy is more than a decade.[21]

The WHO Leprosy fact sheet[60] gives the incubation period of leprosy, from first infection to onset of symptoms, as up to 20 years.

In the European Space Foundation report, incubation period is listed as the first of the list of unknowns that make it impossible to use standard models for the effects of a release and its consequences [61]

Risk mitigation for incubation period[edit | hide | edit source]

The ESF report cite incubation period as one of the risk factors that make it "impossible to model the consequence of the potential release of a Mars organism".[62]

They observe that if the onset is slow and the effects are not unusual, significant spread may occur before the nature of the threat is realised.[63]

They recommend that potential release scenarios (including undetected release) are clearly defined and investigated, and response strategies developed for them.

They considered it critical that such containment strategies are implemented as soon as possible at the local level, and that they should include rapid detection of anomalies, effective warning procedures, and analysis, resistance and mitigation procedures.[64]

Dissenting views of the ICAMSR on back contamination risks of a MSR[edit | hide | edit source]

The International Committee Against Mars Sample Return (ICAMSR)[23] is an advocacy group of scientists campaigning against plans for a fast MSR direct to Earth.

They take the stance that a sample return to the Earth surface should not be carried out at this stage, and that the samples need to be certified as "biosphere safe" in space or in-situ before they are transferred to the Earth’s surface. They cite as their main inspiration, Carl Sagan, who advocated considerable caution before samples are returned to Earth.

The ICAMSR are especially concerned, as was Carl Sagan, that a significant component of risk in biohazard release is the risk of human error, which has happened several times during the Apollo era attempts at containing the lunar samples. In particular they cite the example of an incident during the recovery of the Apollo 11 astronauts at sea. The hatch of the module was opened by divers, while the module was still in the sea, permitting lunar dust and any airborne micro-organisms to exit the module and enter the sea, in breach of the previously established planetary protection protocol for this landing.[65]

Views of the 2002 COMPLEX study of lessons to be learnt from the Apollo quarantine[edit | hide | edit source]

The 2002 COMPLEX study reviewed the experience of the Apollo missions and came to the conclusion that handling of samples was successful even though the quarantine was a failure. They point out that a MSR would not have this human quarantine element.[66][67]

Should a vigorous program of Martian exobiology be carried out first?[edit | hide | edit source]

Carl Sagan recommended that a "vigorous program of unmanned Martian exobiology and terrestrial epidemiology"[21] should be undertaken first, before any Mars sample return.

Michael Meyer, of the NASA exobiology department pointed out that Curiosity " is the first astrobiology mission since Viking in 1976".[68] It is the first mission since Viking to directly search for biosignatures.

Curiosity is limited in its capabilities for exobiology, and s is only a first step in the exobiology research phase. Its "hand lens", though high resolution of 14.5 micrometers per pixel, can't observe endospores or other dormant states directly. A laboratory difraction limited optical microscope for study of cell life typically has a resolution of 0.2 micrometers per pixel. It can't dig far beneath the surface, and it's level of sterilization is not high enough under COSPAR guidelines to study habitats where life might occur in present day Mars.

There are other rovers planned for the future that will build on its results.

Carl Sagan wrote in Cosmos:[69]

“If we wish on Earth to examine samples of Martian soil for microbes, we must, of course, not sterilize the samples beforehand. The point of the expedition is to bring them back alive. But what then? Might Martian microorganisms returned to Earth pose a public health hazard? The Martians of H. G. Wells and Orson Welles, preoccupied with the suppression of Bournemouth and Jersey City, never noticed until too late that their immunological defenses were unavailing against the microbes of Earth. Is the converse possible? This is a serious and difficult issue. There may be no micromartians. If they exist, perhaps we can eat a kilogram of them with no ill effects. But we are not sure, and the stakes are high. If we wish to return unsterilized Martian samples to Earth, we must have a containment procedure that is stupefyingly reliable. There are nations that develop and stockpile bacteriological weapons. They seem to have an occasional accident, but they have not yet, so far as I know, produced global pandemics. Perhaps Martian samples can be safely returned to Earth. But I would want to be very sure before considering a returned-sample mission.”

Probability assessment issues[edit | hide | edit source]

The ESF study found that it is generally agreed that the probability that any martian micro-organism is biohazardous is low. However as no life forms outside of Earth have yet been studied or characterized, it is impossible to do a standard probability assessment.

This is covered in 4.2 Approaching the unknown and considering consequences in the ESF report, under unknown unknowns:

"This lack of knowledge, or uncertainty, prevents definitive conclusions from being reached on major factors that would allow for a real assessment of the risk of contamination posed by an MSR mission, including:

• Whether life exists on Mars or not
• If there are living organisms on Mars, it is not possible to define the probability of a sample (with a given size and mass) actually containing organisms
• If there are living organisms in the sample, it is not possible to definitively assess if (and how) a Mars organism can interact with the Earth’s biosphere."

They concluded that risk assessment has to be carried out by combining knowledge of Earth life with knowledge of Martian geology. They found that it is possible to establish the risk as low, as a consensus of the beliefs of the experts in the field as represented by their experience."

"On the latter point, there is consensus among the scientific community (and among the ESF-ESSC Study Group, as presented above) that the release of a Mars organism into the Earth’s biosphere is unlikely to have a significant ecological impact or other significant effects. However, it is important to note that with such a level of uncertainty, it is not possible to estimate a probability that the sample could be harmful or harmless in the classical frequency definition of probability (i.e. as the limit of a frequency of a collection of experiments). However it is possible to establish the risk as low, as a consensus of the beliefs of the experts in the field as represented by their experience."

Risk assessment survey of microbiologists[edit | hide | edit source]

In 1998, the ecologist Margaret Race of the SETI Institute with Donald MacGregor of Decision Research [70] carried out a survey of microbiologists attending a special five-session colloquium titled “Prospecting for Extraterrestrial Microorganisms and the Origin of Life: An Exercise in Astrobiology”.[71] This survey showed a wide diversity of views amongst microbiologists, when asked for opinions on, for instance, whether there is life on Mars, and whether it could pose a threat to Earth.[72]

Precautionary Principle, Legal situation and need for international public debate[edit | hide | edit source]

By the Precautionary principle, as described in the Wingspread conference.,[73] a key principle in political decision making, and law:

When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.

In this context the proponent of an activity, rather than the public, should bear the burden of proof.

The process of applying the Precautionary Principle must be open, informed and democratic and must include potentially affected parties. It must also involve an examination of the full range of alternatives, including no action [73]

Precautionary principle in the context of Mars Sample Return[edit | hide | edit source]

The ESF-ESSC Study Group on MSR Planetary Protection Requirements studied various versions of the Precautionary Principle in the context of Mars Sample Return.[49] This study found that the ones that were most relevant are:

  • Best Available Technology Precautionary Principle: Activities that present an uncertain potential for significant harm should be subject to best technology available requirements to minimise the risk of harm unless the proponent of the activity shows that they present no appreciable risk of harm.
  • Prohibitory Precautionary Principle: Activities that present an uncertain potential for significant harm should be prohibited unless the proponent of the activity shows that it presents no appreciable risk of harm...

They continue:

...It is not possible to demonstrate that the return of a Mars sample presents no appreciable risk of harm. Therefore, if applied, the Prohibitory Precautionary Principle approach would simply lead to the cancellation of the MSR mission

They therefore argue that the Best Available Technology Precautionary Principle should be used instead.

The definition of Precautionary Principle and the associated conditions presented above align perfectly with the potential risks posed by a Mars sample and the ESF-ESSC Study Group recommends that the Best Available Technology Precautionary Principle is applied when considering the potential release of unsterilised Mars particles.

In this context a required level of risk needs to be determined to assess the technology used. They recommend a one in a million chance of release of a particle from Mars as an acceptable level of risk. Their reasoning is that the chance that the particle is hazardous is already low, and then by making the chance of release as low as one in a million, the combined risk is low enough to be acceptable.

They consider it important to educate the public on the nature of the risk and to monitor and react to public perception of risk of MSR.

Given the fact that possible consequences of an unintended release of a potential Mars life form into the terrestrial biosphere are unknown, it is difficult to predict public reaction to possible risks. Images that the general public associates with Mars life forms are less clear-cut and probably less valenced than those people tend to associate with technological hazards such as nuclear energy and toxic waste. This is reassuring, but it would be advisable to monitor these images and also their relation to the risks people associate with the possible escape of Mars life forms. Given these uncertainties, it seems best to adopt a cautious approach when considering the possible consequences of an unintended release

Legal liability in case of damages[edit | hide | edit source]

The ESF report considered this and came to the conclusion that in the event of a release of the contents of the MSR capsule during return to Earth then the state responsible has unlimited liability in respect to any damages caused.

Under the Liability Convention (United Nations, 1971), the launching State is liable for “damages caused by the space object”. If a sample has detrimental consequences on Earth, it may be considered that the State having launched the spacecraft is liable under this convention (absolute liability without any ceiling either in amount or in time; Liability Convention Article 1 – loss of life, personal injury or impairment; or loss of or damage to property of States or of persons, natural or juridical, or property of international intergovernmental organisations).[5]

They also examined the case where the damages occur as a result of release after the capsule has returned to an Earth laboratory. They concluded that in this case the situation is less clear. The unlimited damage clause may still apply, or they might instead be responsible for an illegal act under general international law in violation of Article IX of the Outer Space Treaty, which doesn't have the same provisions of unlimited liability.

Legal process of approval for Mars sample return[edit | hide | edit source]

Margaret Race has examined in detail the legal process of approval for a MSR.[6] She found that under the National Environmental Policy Act (NEPA) (which did not exist in the Apollo era) a formal environment impact statement is likely to be required, and public hearings during which all the issues would be aired openly. This process is likely to take up to several years to complete.

During this process, she found, the full range of worst accident scenarios, impact, and project alternatives would be played out in the public arena. Other agencies such as the Environment Protection Agency, Occupational Health and Safety Administration, etc, may also get involved in the decision making process. The laws on quarantine will also need to be clarified as applied to this situation.

Then apart from those domestic legal hurdles, there are numerous international regulations and treaties to be negotiated in the case of a Mars Sample Return, especially those relating to environmental protection and health. She concluded that the public of necessity has a significant role to play in the development of the policies governing Mars Sample Return.

Requirement for public debate[edit | hide | edit source]

In addition to the legal requirement, it's been argued that there is a moral requirement for full and open public debate of the issues. The theologan Richard Randolph (in 2009) examined this in detail from a Christian perspective and came up with some recommendations, which are of general interest.[74]

"the problem of risk - even extremely low risk - is exacerbated because the consequences of back contamination could be quite severe ...the consequences might well include the extinction of species and the destruction of whole ecosystems. Humans could also be threatened with death or a significant decrease in life prospects"

The last case of "Humans could also be threatened with death or a significant decrease in life prospects" brings this into the region of existential risks.[75]

He argued that this makes it not a technical problem for scientists to study but an ethical problem requiring extensive public debate at the international level.[76]

He puts forward four criteria to ensure a full and open public debate.

  1. Follow best practises of planetary protection (already being done).
  2. Opportunities should be avaliable for open comment from those concerned about back contamination. These should be taken seriously and NASA should publicly respond to them.
  3. A committee should review the measures, including experts in ecology, biology, chemistry, risk analysis and ethics. Ethicists should represent a diversity of philosophical and religious perspectives.
  4. The entire process must be transparent to the interested public.

Potential value of Mars sample return for science[edit | hide | edit source]

The science potential is the main motivation for the mission, and so needs to be considered in any assessment of MSR plans.

The ESF report highlights the value of a MSR for understanding history of Mars, its geology, volatiles and climate, and for insights into exobiology. They also state that it is an essential preliminary for human explorations to Mars.

They consider that in situ robotic missions will not be able to analyse the samples with the necessary levels of detail. They also point out that any returned samples can be reanalysed many times over using any of the extensive facilities available on Earth.

They also point out its value for engagement of the public with space related activiites, and excitement for the public.[77][78]

See also the section: scientific value for the Mars sample return mission.

Timing concerns for a Mars sample return[edit | hide | edit source]

There are many potential issues concerning the timing of a Mars sample return. Some questions that need to be considered before return of samples to Earth are:

  • Should a Mars receiving facility be constructed first?
  • Should samples be examined for biosignatures and geological context on Mars first?
  • Should samples be examined for signs of life first with advanced tools such as Scanning Electron Microscopes, DNA sequencers, or labelled culture experiments on Mars?
  • Should they be tested for their biohazard potential in Earth like environments on Mars or in orbit (around Mars, the Earth or the Moon), before return to Earth?

Most researchers are agreed on the first two points but there are dissenting views on the remaining two.

Mainstream view - a MSR can be undertaken at an early stage, but needs additional precautions[edit | hide | edit source]

Many scientists accept that a Mars Sample Return can be done with an acceptably low probability of an adverse outcome, provided that the recommendations of the study groups are carried out. On this view, then the Mars receiving facility needs to be up and running two years before the return. However there is no need for detailed examination of the samples before return. A record of the geological context of each sample is essential. Some biosignature testing is recommended to help select interesting samples.[11]

ICAMSR Charter - certified safe in situ or in space first[edit | hide | edit source]

The ICAMSR have as their main goal, that samples are certified safe in situ or in space first before they are returned to Earth.

Having planetary/cometary samples certified as "biosphere safe" in space or in-situ before they are transferred to the Earth’s surface is our main goal and intention.[79]

Issues to do with selection of samples of biological interest[edit | hide | edit source]

Recommendation of continued in situ study first - white paper for decadal review[edit | hide | edit source]

This is a white paper submitted for the decadal review by eight authors from the NASA Jet Propulsion Laboratory, the Scripps Institution of Oceanography, SETI Institute, NASA Ames Research Center and the University of California Berkeley.

These authors argue that we do not yet know enough to intelligently select samples for return. They recommend a "Follow the Nitrogen strategy for in situ exploration".

They recommend that a MSR should be delayed until unambiguous biomarkers are identified in prospective Mars samples. They argue that there is a risk that samples returned at our current level of understanding may in the worst case be "as ambiguous with respect to the search for life as ALH84001." [25] [80]

For return of biologically interesting samples, they require ability to identify, in situ:

  • Biomarkers and unequivocal biosignatures stable over geological timescales. Examples: ability to detect chirality, and primary amine distribution.
  • Samples suitable for preserving life, and of preserving organics without significant degradation over geological time periods. Examples: sulfates, haliites, clays and the polar layered deposits
  • Nitrogenous organic compounds
  • Minute trace amounts of organics

They also recommend:

  • Any extraction methods used must preserve the target organic molecules with low degradation
  • Drilling must be carried out to the greatest depth possible, to allow for greatest chance of success for detecting organics and biosignatures.

Paige 's view[edit | hide | edit source]

Paige raises similar concerns.[26] He refers to a 1996 study requested by Michael Meyer of NASA’s Exobiological Program Office.[81] This divided Mars exploration into five phases including:[26]

  • Phase 1. Global Reconnaissance, focusing on past and present role of water, and identification of sites for detailed study.
  • Phase 2. In-Situ Exploration of Promising Sites, focusing on geologic, mineralogic, elemental, and isotopic characteristics, abundance and distribution of volatile species and organic molecules.
  • Phase 3. Deployment of exobiologically-focused experiments, and search for biomarkers of formerly living organisms, and extant life.
  • Phase 4. Robotic Return of Martian Samples to Earth, to improve characterization of organic compounds, and verify any evidence for biomarkers and extant life discovered in Phase 3.
  • Phase 5. Human exploration for detailed scientific characterizations of sites of unusual biologic interest, or inaccessible to robotic exploration.

Paige reasons that Mars exploration is still in phases 1 and 2, and that we need to complete phase 3 before going on to phase 4.[26][82]

Suggested near future methods for selection of samples of biological interest[edit | hide | edit source]

Some of the decadal review white paper, and Paige's concerns (but not all) have been addressed by the Final report of the MSR End-to End International Science Analysis Group in 2011. They stress the importance of observations to understand the geological context, They also plan to include the ESA Pasteur payload (developed for ExoMars) which includes some life detection instruments. It will for instance able for instance to detect many specific molecules likely to be associated with past or present life, with its Life Marker Chip.[83][84][85]

The focus of this report was on missions they considered practical, so, unlike Jeffrey Bada's suggestion, they don't require deep drilling, and don't require the MSR to be delayed until unambiguous biosignatures are found.

"Finally, for the purposes of this study, the vision of the MSR Campaign was constrained by what was considered to be practical ... Thus, objectives that might require high latitudes, high elevations, deep (>2 m) drilling, and large sample masses, for example, were given lower priority. The intent was not to provide a prioritized list in the abstract, but one that could be used to guide a sample return campaign in the context of our current knowledge and expectations of future engineering and fiscal resources." [84]

Issues to do with contamination of a returned sample by terrestrial DNA (Craig Venter)[edit | hide | edit source]

Craig Venter (famous for sequencing the human genome) is in process of developing a miniaturized gene sequencer small enough to fit on a rover to Mars. Craig Venter's view is that this is best done in situ on Mars.[27]

His motivation for this is that current gene sequencers are now so sensitive, that if a single micro-organism from Earth landed on the sample returned from Mars, it would ruin any experiments to test for presence of martian DNA on the sample.

Space Studies Board recommendations to avoid biological contamination of the returned sample[edit | hide | edit source]

The Space Studies Board raise similar concern but believe biological contamination of the returned sample can be avoided by suitable decontamination procedures. This is from the 2011 review of the Space Studies Board,[67]

It is possible that traces of life on Mars may be very rare and heterogeneously distributed, and the concentration of organics in the soil may be very low. Thus, it is essential to avoid biological contamination as well as organic contamination of Mars and of the collected samples.

Robert Zubrin's view that back contamination risk has no scientific validity[edit | hide | edit source]

Robert Zubrin, president of the Mars society, presented this view in a published article[2] and in interview. This is a transcript of an interview with him on March 30, 2001. First he refers to research that shows that the interior of a meteorite from Mars can remain below 40C throughout it's journey to Earth, and so is not sterilized, and then continues.

If you want to get a sense of this. Close to two trillion kilograms of Martian material has been transferred to Earth over the past 3.5 billion years in which the surface of Earth could support life. And from at least a thousand different sites on the surface of Mars. And so the stuff about back contamination simply has no scientific validity whatsoever.[3]

His current view however is that no MSR is needed at all before human colonization, see #Robert Zubrin's view that there is no need for a MSR before human colonization of Mars

NRC conclusions on relevance of martian meteorites to back contamination risks[edit | hide | edit source]

This is considered in the NRC report. They observe that a sample return is returned directly from Mars over a short time period, with no impact shock and protected in a capsule. They observe that though meteorites from Mars reach Earth every year, they are ejected from Mars only rarely in the larger impacts (large impacts are needed to achieve escape velocity).

Taking into account theoretical models, and measurements of aging of meteorites through cosmic radiation, they conclude that when there is a large impact on Mars, most of the debris takes a time period of between hundreds of thousands and millions of years to reach Earth, and during that time period much of any dormant life is sterilized by cosmic radiation. A small fraction, 0.01% is expected to reach Earth in less than a century, and some of the material is only lightly shocked. So transfer of life from Mars to Earth does seem possible but likely to happen rarely, and more common in the early solar system.

They considered reports of micro-organisms with radiation resistance adaptations that have been suggested as possible candidates for micro-organisms that have come from Mars originally, and conclude:

"Despite suggestions to the contrary, it is simply not possible, on the basis of current knowledge, to determine whether viable martian life forms have already been delivered to Earth. Certainly in the modern era, there is no evidence for large-scale or other negative effects that are attributable to the frequent deliveries to Earth of essentially unaltered martian rocks. However, the possibility that such effects occurred in the distant past cannot be discounted. Thus, it is not appropriate to argue that the existence of martian meteorites on Earth negates the need to treat as potentially hazardous any samples returned from Mars via robotic spacecraft."[35]

Alternatives to an early return of Mars samples to the Earth's surface[edit | hide | edit source]

Several suggestions have been made to deal with the scientific, or biohazard, concerns about an early sample return to Earth.

There are proposals to study the sample extensively on the surface of Mars. There are also proposals to return the sample to quarantine facilities in Mars orbit or to Earth orbit, either before or after study on the surface.

With most of these approaches, Mars sample return would be expected eventually. The timing depends on the approach. For instance with the Bada and Paige suggestions, sample return would occur once samples are found with clear evidence of present or past life, or evidence of biosignatures in the present or past. With the telerobotics approach, sample return is done to Earth after preliminary study in orbit around Mars. With Zubrin's approach, sample return is done at a much later stage after human colonization of Mars. With Levin's approach, sample return is done after a series of biohazard testing experiments have been completed in situ on Mars, and in orbit.

Extensive study of the samples first on the Mars surface[edit | hide | edit source]

Exomars Urey Instruments

We have seen that several authors recommended in situ survey first and and Paige predicted that new instruments under development will make it possible to analyse rocks in situ on Mars, permitting a flexible approach where rovers can make new choices of targets of potential biological interest on the surface of Mars based on findings for the samples encountered earlier in the mission.[25][26]

This is list of a few of the instruments under development for future Mars missions that permit or will permit preliminary study of samples with greater sensitivity than any instruments currently in use on the rovers.

  • NASA Marshall Space Flight Center is leading a research effort to develop a Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM) for future lunar and martian missions.[86]
  • Jonathan Rothberg, and J. Craig Venter, are separately developing solutions for sequencing alien DNA directly on the Martian surface itself.[87][88]
  • Levin is working on updated versions of the Labeled release instrument flown on Viking. For instance versions that rely on detecting chirality. This is of special interest because it can enable detection of life even if it is not based on standard life chemistry.[89]
  • The Urey Mars Organic and Oxidant Detector instrument for detection of biosignatures due to be flown on ExoMars in 2018. It is designed with much higher levels of sensitivity for biosignatures than any previous instruments[25][90][91]

Vigorous study of the Mars surface instead of a sample return[edit | hide | edit source]

Dirk Schulze-Makuch and Robert Zubrin have both taken this view, that a vigorous continuing study of the Mars surface would be more beneficial than a MSR at the current stage of exploration of Mars, though for rather different reasons.

Dirk Schulze-Makuch's view that from an atrobiological standpoint, in-situ research is better and cheaper than MSR[edit | hide | edit source]

This view was given in an interview for space.com of astrobiologist Dirk Schulze-Makuch [92]

"I disagree with the high priority on sample return," said astrobiologist Dirk Schulze-Makuch of Washington State University in Pullman.

"Our in-situ [on-the-spot] capabilities are so much better nowadays than, let's say during Viking lander (1970s) times," Schulze-Makuch said. "We could address with an in-situ mission whether microbial life is present on Mars."

Sample return missions are so much more costly, Schulze-Makuch said, "and the only thing that would be advantageous, in my view, is to get an absolute age scale via radioactive dating of Martian rocks," Schulze-Makuch said, "but from an astrobiological viewpoint, [an] in-situ mission would be better and cheaper."

He (along with other researchers) has published his own proposal for a mission called BOLD to send many penetrator probes to Mars to sample it sub surface and seek signs of life [93][94][95]

Robert Zubrin's view that there is no need for a MSR before human colonization of Mars[edit | hide | edit source]

Another advocate of vigorous study on the surface in place of a MSR at the current stage of exploration of Mars is Robert Zubrin, president of the Mars Society. He sees value in scientific study of Mars before a human colonization, but is of the opinion that the same objectives are better met using a vigorous program of robotic exploration.

He suggests an initial exploration stage with many rovers on the same model as Curiosity. As additional motivation for his approach, he suggests that humans post colonization of Mars can do far better sample return missions than a robotic mission can do now.:[96][97] [98]

Study In Situ followed by Return to the ISS or Earth orbital laboratory first[edit | hide | edit source]

Gilbert Levin is motivated by concerns for back contamination of Mars, following the inspiration of Carl Sagan. For this reason, he recommends a 10 step sequence for returning Martian samples to Earth[99]

His suggestion starts with a series of tests for micro-organisms in situ on Mars, including tests for biohazard potential to whatever extent is possible on Mars. They are then returned to the ISS.

Once in the ISS they need to be examined in secure biohazard facilities by volunteer scientists who are willing to give up their lives in the remote chance that a hazard is found that is of danger to life on Earth.

Finally, if they pass all the tests, they can be returned to secure biohazard labs on Earth for further testing (similarly to the ESF / NRC proposals). Once the samples are returned to Earth he recommends that laboratories should be provided for researchers all in the same location, rather than to send the samples to researchers in other locations for testing.

Issues with the use of quarantine periods in space to contain any biohazard[edit | hide | edit source]

A 1997 study by the National Research Council found some issues with the use of humans in quarantine which would need to be addressed with any proposal that involves human quarantine, such as Levin's. First, the study raised the issue that it would be hard to know for sure if any detected anomaly was the result of contamination. How, they say, could sufficient certainty be achieved to justify destroying the returning spacecraft and its crew?[100]

In the case of NASA's Lunar quarantine at the time of Apollo 11, one of the guiding principles permitted breach of quarantine in the case of danger to human life:[101]

2. The preservation of human life should take precedence over the maintenance of quarantine.

Indeed in practise containment was breached for a lesser reason than preservation of life; it was breached in order to prevent seasickness of the Apollo 11 astronauts during the sea landing. As Carl Sagan wrote about this incident:[102]

"The one clear lesson that emerged from our experience in attempting to isolate Apollo-returned lunar samples is that mission controllers are unwilling to risk the certain discomfort of an astronaut – never mind his death – against the remote possibility of a global pandemic."

So the issue here is whether it is politically or humanly feasible to have a policy that puts preservation of quarantine at a higher priority than preservation of the life of individual astronauts. If not, then it is unclear how much extra protection quarantine provides.

Another issue raised with this approach is that infection might not be the only biohazard to contain, since a returning organism could cause long term changes in our environment that does not turn up during a quarantine period with humans.[100] There is also the issue of the latency period, that the astronauts may not show any signs of infection until after return from Earth.

The NRC study concluded that as a result of these issues, the human quarantine approach does not give guarantee of containment of any issues found.[100][103]

Jeffrey Kargel in "Mars - A Warmer, Wetter Planet" considers an alternative possibility to death of the astronauts when he discusses the possibility of an indefinite quarantine in the case that an issue is found during the quarantine period. He has doubts about the workability of an indefinite quarantine on the Moon, and feels that a quarantine on a space station can't remain isolated indefinitely due to it's low orbit and need to resupply, and suggests that "the most effective and practical lifetime quarantine would be on Mars".[104]

Study via telepresence from Mars orbit, followed by return of the sample to Mars orbit[edit | hide | edit source]

Telerobotics exploration on Mars and Earth

During the “Exploration Telerobotics Symposium" in 2012 experts on telerobotics from industry, NASA and academics met to discuss telerobotics, and its applications to space exploration. Amongst other issues, particular attention was given to Mars missions and a Mars sample return.

They came to the conclusion that telerobotic approaches could permit direct study of the samples on the Mars surface via telepresence from Mars orbit, permitting rapid exploration and use of human cognition to take advantage of chance discoveries and feedback from the results obtained so far.[105]

They found that telepresence exploration of Mars has many advantages. The astronauts have near real-time control of the robots, and can respond immediately to discoveries. It also prevents contamination both ways and has mobility benefits as well.[106]

Return of the sample to orbit has the advantage that it permits analysis of the sample without delay, to detect volatiles that may be lost during a voyage home. This was the conclusion of a meeting of researchers at the NASA Goddard Space Flight Center in 2012. [107]

Telerobotics exploration of Mars

"One possible scenario for surface exploration of Mars via LLT could be the deployment of twin telerobotic rovers on the surface with high-definition visual tools to allow low-latency communication and rapidly adaptable operation from an on-orbit crew for field astrobiology. Such “tele-rovers” could be equipped with instruments for detailed in situ reconnaissance and capabilities for recovering and sending selected samples to the human-tended on-orbit spacecraft for preliminary screening by means of lab analysis by resident astronauts. In the case of samples of biological significance, very rapid encapsulation and recovery of the sample materials at the spacecraft in orbit are required and this is enabled by this approach. Most of the required technology already exists for terrestrial telerobotics exploration of Earth, although the TRL would have to be advanced and validated for operations on Mars"[105]

For more about exploration of Mars via telepresence, see Exploration of the surface from orbit, via telerobotics and telepresence

Advocacy of early Mars sample return[edit | hide | edit source]

Some researchers and mission planners have put forward strong advocacy for an early Mars sample return. In particular this was one of the main conclusions of the 2011 decadal survey, an extensive survey of the community of active planetary scientists carried out every ten years in the USA.

The 2011 survey strongly advocated a Mars Sample Return program as the top flagship mission, to be carried out in several stages (with the mission to Europa proposal second).

"The view expressed by the Mars community is that Mars science has reached the point where the most fundamental advances will come from study of returned samples."[108]

In this survey, it was descoped due to cost considerations but the science value was considered high.[109]

In favour of the value of sample return they cite results from previous sample returns and their analogues (e.g., of meteorites, the Moon, cometary dust, and the solar wind) and point out that the Martian meteorites known are from a limited range of rock types, so that carefully selected samples returned from Mars can greatly increase our understanding of the planet.[110]

These views were later summarizes as:[11]

The Mars community, in their inputs to the decadal survey, was emphatic in their view that a sample return mission is the logical next step in Mars exploration. Mars science has reached a level of sophistication that fundamental advances in addressing the important questions above will only come from analysis of returned samples.

In the summary of the final report of the Mars Program Planning Group in September 2012,[111] two main possibilities were considered:

  • Search for signs of past life with samples collected from a site identified using exising data and returned to Earth for analysis (pathways A1 and A2)
  • Sample Return commences only after in situ measurements and sampling of multiple sites and Science Community decision process as to which to return to Earth (pathway A3)

They comment that the first option (their pathways A1 or A2) is most directly responsive to the NRC Decadal Survey recommendations.

Anteus (1978)

Historical background[edit | hide | edit source]

The idea of a Mars Sample Receiving laboratory was first studied in 1978. The idea then was for an orbiting quarantine facility called Anteus to receive the samples.[7]

Other proposals were explored in the 1980s, including direct entry of sample container to Earth's atmosphere, recovery by the space shuttle, recovery to space station, recovery to a dedicated Antaeus space station, and several intermediate proposals.[112]

See also[edit | hide | edit source]

This page separated out into separate sections:

[Ed: Not sure what to do about this yet]

References[edit | hide | edit source]

  1. "Assessment of Planetary Protection Requirements for Mars Sample Return Missions", National Research Council, 2009, chapter 5, "The Potential for Large-Scale Effects". "Thus, a key question posed to the committe is whether a putative martian organism or organisms, inadvertently released from containment, could produce large-scale negative pathogenic effects in humans or have a destructive impact on Earth's ecological system or environments." (page 45) They divide it into 3 categories
    • Large-scale negative pathogenic effects in humans;
    • Destructive impacts on Earth's ecological systems or environments; and
    • Toxic and other effects attributable to microbes, their cellular structures, or extracellular products.


    (page 45)

    They conclude that the last one is unlikely. But for the other two

    The committee found that the potential for large-scale negative effects on Earth's inhabitants or environment by a returned martian life form appears to be low, but is not demonstrably zero.

    (page 48)
  2. 2.0 2.1 Robert Zubrin "Contamination From Mars: No Threat", The Planetary Report July/Aug. 2000, P.4–5
  3. 3.0 3.1 transcription of a tele-conference interview with ROBERT ZUBRIN conducted on March 30, 2001 by the class members of STS497 I, "Space Colonization"; Instructor: Dr. Chris Churchill
  4. 4.0 4.1 "5: "The Potential for Large-Scale Effects"". Mars Sample Return backward contamination - strategic advice (PDF) (Report). European Science Foundation. 2012. RECOMMENDATION 10: Considering the global nature of the issue, consequences resulting from an unintended release could be borne by a larger set of countries than those involved in the programme. It is recommended that mechanisms dedicated to ethical and social issues of the risks and benefits raised by an MSR are set up at the international level and are open to representatives of all countries.  line feed character in |quote= at position 22 (help)
  5. 5.0 5.1 Mars Sample Return backward contamination – Strategic advice and requirements see 7.2: Responsibility and liability of States
  6. 6.0 6.1 M. S. Race Planetary Protection, Legal Ambiguity, and the Decision Making Process for Mars Sample Return Adv. Space Res. vol 18 no 1/2 pp (1/2)345-(1/2)350 1996
  7. 7.0 7.1 DAVID S. F. PORTREE Antaeus Orbiting Quarantine Facility (1978) 7th July, 2012
  8. Dwayne Brown, Sarah DeWitt NASA Announces Robust Multi-Year Mars Program; New Rover to Close Out Decade of New Missions (note, proposed mission only, was postponed)
  9. Wall, Mike (September 27, 2012). "Bringing Pieces of Mars to Earth: How NASA Will Do It (note, proposed mission only)". Space.com. Retrieved September 28, 2012. 
  10. Staff Writers (Oct 10, 2012). "China to collect samples from Mars by 2030". Mars Daily via Xinhua. 
  11. 11.0 11.1 11.2 11.3 Vision and Voyages for Planetary Science in the Decade 2013-2022 (PDF) (Report). 2013. The site will be selected on the basis of compelling evidence in the orbital data for aqueous processes and a geologic context for the environment (e.g., fluvial, lacustrine, or hydrothermal). The sample collection rover must have the necessary mobility and in situ capability to collect a diverse suite of samples based on stratigraphy, mineralogy, composition, and texture.83 Some biosignature detection, such as a first-order identification of carbon compounds, should be included, but it does not need to be highly sophisticated, because the samples will be studied in detail on Earth 
  12. "2: "The Potential for Past or Present Habitable Environments on Mars"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. 
  13. European Science Foundation - Mars Sample Return backward contamination - strategic advice July, 2012, ISBN 978-2-918428-67-1 - see Back Planetary Protection section. (for more details of the document see abstract )
  14. Jeremy Hsu Keeping Mars Contained (illustrated with the FLAD, DC and LAS Mars Receiving Facility designs Astrobiology Magazine, 12/03/09
  15. Mars Sample Return: Issues and Recommendations (Planetary Protection Office Summary) (Report). Planetary Protection Office. 1997. The potential for large-scale effects, either through pathogenesis or ecological disruption, is extremely small. Thus, the risks associated with inadvertent introduction of exogenous microbes into the terrestrial environment are judged to be low. However, any assessment of the potential for harmful effects involves many uncertainties, and the risk is not zero. ... The SSB task group strongly endorses NASA’s Exobiological Strategy for Mars Exploration (NASA, 1995). Such an exploration program, while likely to greatly enhance our understanding of Mars and its potential for harboring life, nonetheless is not likely to significantly reduce uncertainty as to whether any particular returned sample might include a viable exogenous biological entity-at least not to the extent that planetary protection measures could be relaxed. 
  16. Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. 
  17. NASA Office of Planetary Protection
  18. Mars Sample Return: Issues and Recommendations (Planetary Protection Office Summary) Task Group on Issues in Sample Return. National Academies Press, Washington, DC (1997)
  19. "7: "Sample-Receiving Facility and Program Oversight"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 59. It has been estimated that the planning, design, site selection, environmental reviews, approvals, construction, commissioning, and pre-testing of a proposed SRF will occur 7 to 10 years before actual operations begin.17,18,19 In addition, 5 to 6 years will likely be required for refinement and maturation of SRF-associated technologies for safely containing and handling samples to avoid contamination and to further develop and refine biohazard-test protocols. Many of the capabilities and technologies will either be entirely new or will be required to meet the unusual challenges of integration into an overall (end-to-end) Mars sample return program.  Unknown parameter |http://www.nap.edu/openbook.php?record_id= ignored (help)
  20. 20.0 20.1 "2: "The Potential for Past or Present Habitable Environments on Mars"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 28. The present committee found that the knowledge gained from both orbital and landed missions conducted over the past decade, combined with findings from studies of martian meteorites, has enhanced the prospect that habitable environments were once widespread over the surface of Mars. In addition, the potential for modern habitable environments, both as transient surface environments asnd as stable habitats in the deep subsurface, is much better understood. This understanding has, in turn, enhanced the possibility that living entities could be present in samples returned from Mars. Therefore the committee concurs with and expands on the 1997 recommendation that no uncontained martian materials should be returned to Earth unless sterilized. 
  21. 21.0 21.1 21.2 21.3 21.4 21.5 21.6 Carl Sagan,The Cosmic Connection - an Extraterrestrial Perspective (1973) ISBN 0521783038
  22. 22.0 22.1 22.2 Barry E. DiGregorio The dilemma of Mars sample return August 2001 Vol. 31, No. 8, pp 18–27. - for the quote from Carl Woese see his reference 54
  23. 23.0 23.1 International Committee Against Mars Sample Return.
  24. 24.0 24.1 24.2 Joshua Lederberg Parasites Face a Perpetual Dilemma Volume 65, Number 2, 1999 / American Society for Microbiology News 77.
  25. 25.0 25.1 25.2 25.3 Jeffrey L. Bada, Andrew D. Aubrey, Frank J. Grunthaner, Michael Hecht, Richard Quinn, Richard Mathies, Aaron Zent, John H. Chalmers Seeking signs of life on mars: in situ investigations as prerequisites to sample return missions Independent Contribution to the Mars Decadal Survey Panel
  26. 26.0 26.1 26.2 26.3 26.4 Mars Exploration Strategies: Forget About Sample Return D. A. Paige, Dept. of Earth and Space Sciences, UCLA, Los Angeles, CA 90095
  27. 27.0 27.1 Genome Hunters Go After Martian DNA Antonio Regalado, Biomedicine News, MIT Technology Review, October 18, 2012
  28. Carl Woese The Birth of the Archaea: a Personal Retrospective
  29. Assessment of Planetary Protection Requirements for Mars Sample Return Missions, National Research Council, 2009
  30. "5: The Potential for Large-Scale Effects"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 45. While the existence of habitable conditions provides no guarantee that life ever originated on Mars, the possibility has increased that a martian life form, whether active, dormant, or fossil, could be included in a sample returned from Mars. 
  31. "Assessment of Planetary Protection Requirements for Mars Sample Return Missions", National Research Council, 2009, chapter 3, "Advances in Microbial Ecology".
  32. "4: "The Potential for Finding Biosignatures in Returned Martian Samples"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 41. Geobiological studies of both modern and ancient Mars-relevant environments on Earth have highlighted the potential for samples returned from Mars to contain viable microorganism or their fossilized remains, while supporting the development of new approachs for in situ and laboratory detection of biosignatures in a variety of geological materials. 
  33. "5: The Potential for Large-Scale Effects"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 46. As reviewed in Chapter 3, extreme environments on Earth have not yet yielded any examples of life forms that are pathogenic in humans. However, it is worth noting in this context that interesting evolutionary connections between alpha proteobacteria and human pathogens have recently been demonstrated for natural hydrothermal environments on Earth, suggesting that evolutionary distances between nonpathogenic and pathogenic organisms may be quite small in some instances. It follows that, since the potential risks of pathogenesis cannot be reduced to zero, a conservative approach to planetary protection will be essential, with rigorous requirements for sample containment and testing protocols. 
  34. "5: "The Potential for Large-Scale Effects"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 47. If the 1:100 ratio is accepted as being representative, then of the roughly 500 meteorites that fall on Earth every year, perhaps five are from Mars. 
  35. 35.0 35.1 "5: "The Potential for Large-Scale Effects"". Assessment of Planetary Protection Requirements for Mars Sample Return Missions (Report). National Research Council. 2009. p. 47. Transit to Earth may present the greatest hazard to the survival of any microbial hitchhikers. Cosmic-ray-exposure ages of the meteorites in current collections indicate transit times of 350,000 to 16 million years. However theoretical modeling suggests that about 1 percent of the materials ejected from Mars are captured by Earth within 16,000 years and that 0.01 percent reach Earth within 100 years. Thus, survival of organisms in meteorites, where they are largely protected from radiation, appears plausible. If microorganisms could be shown to survive conditions of ejection and subsequent entry and impact, there would be little reason to doubt that natural interplanetary transfer of organisms is possible and has, in all likelihood, already occurred. ...It should be noted that martian materials transported to Earth via a sample return mission will spend a relatively short time (less than a year) in space - all the while protected in containers. (Note that researchers have yet to discover compelling evidence of life in any meteorite, martian or otherwise.) Thus the potential hazards posed for Earth by viable organisms surviving in samples is significantly greater with a Mars sample return than if the same organisms were brought to Earth via impact-mediated ejection from Mars.  line feed character in |quote= at position 765 (help) Cite error: Invalid <ref> tag; name "nrc2009_5p48" defined multiple times with different content
  36. "Assessment of Planetary Protection Requirements for Mars Sample Return Missions", National Research Council, 2009, chapter 5, "The Potential for Large-Scale Effects". "Thus, a key question posed to the committe is whether a putative martian organism or organisms, inadvertently released from containment, could produce large-scale negative pathogenic effects in humans or have a destructive impact on Earth's ecological system or environments." (page 45) They divide it into 3 categories
    • Large-scale negative pathogenic effects in humans;
    • Destructive impacts on Earth's ecological systems or environments; and
    • Toxic and other effects attributable to microbes, their cellular structures, or extracellular products.


    (page 45)

    They conclude that the last one is unlikely. But for the other two

    The committee found that the potential for large-scale negative effects on Earth's inhabitants or environment by a returned martian life form appears to be low, but is not demonstrably zero.

    (page 48)
  37. Mars Sample Return backward contamination – Strategic advice and requirements see 3. Life as we know it and size limits
  38. 38.0 38.1 Size Limits of Very Small Microorganisms: Proceedings of a Workshop ( 1999 ) see Page 2 for the quote, "Given the uncertainties inherent in this estimate the panel agreed that 250 ± 50 nm as a reasonable lower limit for life as we know it"
  39. 39.0 39.1 European Science Foundation - Mars Sample Return backward contamination - strategic advice - (see Life as we know it and size limits) - February 23, 2010
  40. David Prangishvili, Patrick Forterre and Roger A. Garrett Viruses of the Archaea: a unifying view - 2006
  41. Quote from the ESF report to assist editors in verifying the paraphrase

    However, as stated above viruses are not able to reproduce by themselves but need a host organism. For potential consequences on the Earth’s biosphere either these putative virus-type Mars entities have to be able to use a terrestrial cell as host, which would require a very specific and sophisticated adaptation to these cell types, or the putative Martian host has to be present in the same Martian sample and has to be alive and metabolically active to enable the replication of that entity

  42. Quote from the ESF report to assist editors in verifying the paraphrase In 3.5 Gene transfer agents (GTAs) they write:

    GTAs resemble small bacteriophages, ranging in size from 30 to 80 nm with 4.4 to 13.6 kb DNA. A universal characteristic of GTAs is that they randomly incorporate segments of the host genome into the viral capsid where they can transfer this to different hosts, including phylogenetically unrelated bacteria and archaea, without resulting in lysis of the host cell. In this manner, it is believed that it is possible for GTAs to incorporate any of the host genes during replication...

    While many questions remain about the origin of GTAs, their prevalence in different species of bacteria and archaea, and their host range including cross-domain infection, there is evidence that a large portion of marine viromes consist of GTAs. Surprisingly, it is now estimated that GTA transduction rates are more than a million times higher than previously reported for viral transduction rates in marine environments. Clearly, GTAs are a major source of genetic diversity in marine bacteria....

  43. Amy Maxmen Virus-like particles speed bacterial evolution published online 30 September 2010
  44. Lauren D. McDaniel, Elizabeth Young, Jennifer Delaney, Fabian Ruhnau, Kim B. Ritchie, John H. Paul High Frequency of Horizontal Gene Transfer in the Oceans Science 1 October 2010: Vol. 330 no. 6000 p. 50 DOI: 10.1126/science.1192243
  45. Quote from the New Scientist article to assist editors in verifying the paraphrase

    The researchers sealed these GTAs in bags filled with seawater collected from different coastal environments, and floated the bags in the ocean to mimic natural conditions as closely as possible. After incubation overnight, up to 47% of the bacteria living in the seawater-filled bags had incorporated the particles and their genetic contents into their genomes

  46. Quote from the ESF report to assist editors in verifying the paraphrase In 3.6 From new knowledge to new requirements:

    The Study Group also concurs with another conclusion from the NRC reports that the potential for large-scale effects on the Earth’s biosphere by a returned Mars life form appears to be low, but is not demonstrably zero. It adds that if this risk appears to be low for free-living self-replicating organisms, considering their specificities and replication requirements, the potential risk posed by virus-type and gene transfer agent-type entities can be considered to be far lower and almost negligible, but still cannot be demonstrated to be zero.

  47. Quotes from the ESF report to assist editors in verifying the paraphrase

    Unsterilised particles smaller than 0.01 µm would be unlikely to contain any organisms, whether free-living self-replicating (the smallest free-living self-replicating microorganisms observed are in the range of 0.12–0,2 µm, i.e. more than one order of magnitude larger), GTA-type (the smallest GTA observed is 0,03 µm, i.e. three times larger) or virus-type (the smallest GTA observed is 0,017 µm, i.e. almost twice as large). This level should be considered as the bottom line basic requirement when designing the mission systems and operation.

    They then go on in view of the almost negligible chance of a GTA potential for large-scale effects on the Earth's biosphere, that

    The release of particles larger than 0.01 µm but smaller than 0.05µm can be considered as tolerable if it can be demonstrated that such a range is the best achievable at reasonable cost.

    They recommend that in that case the requirements would need to be independently reviewed by a panel of experts to determine if it is the best that can be achieved at reasonable cost and if the risk is tolerable.

    Any release of a single unsterilised particle larger than 0.05 µm is not acceptable. The ESF-ESSC Study group considers that a particle smaller than 0.05 µm would be unlikely to contain a free-living microorganism, but that larger particles may bear such an organism. As self-replicating free-living organisms are likely to be the main concern following a release event, the study group considers that the release of a particle larger than 0.05 µm is not acceptable under any circumstance.

  48. Quote from the ESF report to assist editors in verifying the paraphrase

    Based on our current knowledge and techniques (especially genomics), one can assume that if the expected minimum size for viruses, GTAs or freeliving microorganisms decreases in the future, and this is indeed possible, it will be at a slower pace than over the past 15 years.However, no one can disregard the possibility that future discoveries of new agents, entities and mechanisms may shatter our current understanding on minimum size for biological entities. As a consequence, it is recommended that the size requirement as presented above is reviewed and reconsidered on a regular basis.

  49. 49.0 49.1 49.2 49.3 49.4 European Science Foundation - Mars Sample Return backward contamination - strategic advice February 23, 2010, ISBN 978-2-918428-67-1 - see Back Planetary Protection section. (for more details of the document see abstract ) Cite error: Invalid <ref> tag; name "esf2010_PP" defined multiple times with different content
  50. Jeremy Hsu Keeping Mars Contained Astrobiology Magazine, 12/03/09
  51. 51.0 51.1 "4.7 Potential verification methods"". Mars Sample Return backward contamination - strategic advice (PDF) (Report). European Science Foundation. 2012. While the Study Group was not tasked with considering human factors, it has to be highlighted that the use of human handling in this process and the transport itself entails the risk of human error and the potential for accidental release. For this reason, care must be taken to minimise human interaction with the sample and to provide adequate protection via transport containment to guard against an accident during transport to the curation facility. 
  52. Mars Sample Return Using Commercial Capabilities: ERV Trajectory and Capture Requirements Details of one way such a return could be done, by first returning sample to moon orbit. There the return vehicle is left in orbit around the Moon and the sample is then transferred to the interior of a larger container sent from Earth on a SpaceX dragon capsule. This larger capsule is then sealed and returned to Earth.
  53. Mars Sample Return: Mars Ascent Vehicle Mission and Technology Requirements NASA Technical Report
  54. A Draft Test Protocol for Detecting possible biohazards in martian samples returned to Earth (PDF) (Report). NASA. 2002. Procedures for handling a breach of the SRF due to different causes (e.g. leak, disaster, security breach etc) should be considered in he development of plans for handling a breach. Concerns about security should also be reconsidered, epecially in view of the potential disruptive activities of any terrorist or 'radical' groups that may be opposed to sample return (page 101) .... The breach could be the result of an accident or a crime - as a result of activity either outside or within containment (page 104) 
  55. Assessment of Planetary Protection Requirements for Mars Sample Return Missions (2009) Space Studies Board
  56. Preliminary Planning for an International Mars Sample Return Mission Report of the International Mars Architecture for the Return of Samples (iMARS) Working Group, June 1, 2008
  57. Jeremy Hsu Keeping Mars Contained Astrobiology Magazine 12/03/09
  58. Beaty DW, Allen CC, Bass DS, Buxbaum KL, Campbell JK, Lindstrom DJ, Miller SL, Papanastassiou DA. Planning considerations for a Mars Sample Receiving Facility: summary and interpretation of three design studies. Astrobiology. 2009 Oct;9(8):745-58. doi: 10.1089/ast.2009.0339.
  59. Mars Sample Return: Issues and Recommendations(1997)] Task Group on Issues in Sample Return, National Research Council (page 31)
  60. Leprosy Fact Sheet World Health Organization
  61. European Science Foundation - Mars Sample Return backward contamination - strategic advice - (see 5.3 Direct consequences for human health) - July, 2012
  62. quote and paraphrase to assist editors in verifying accuracy of the main text paraphrase
    • "Incubation period
    • Transmissibility from person to person/number of secondary cases per infected individual
    • Time window of transmission
    • Case fatality rate
    • Hospitalisation of patients – hospitals can increase transmission and amplify outbreaks
    • Transmission routes (aerosol, ingestion, etc.)
    • Survival/reproduction in the environment
    • Can it infect animals/plants
    • Duration of the symptomatic phase"

    Since all these factors are unknown, they concluded that "it is impossible to model the consequence of the potential release of a Mars organism".

  63. quote and paraphrase to assist editors in verifying accuracy of the main text paraphrase

    "From a crisis management position, if the effects of the release are unusual and of rapid onset, it is most likely that the causative agent will be identified fairly quickly and actions can be taken to try to limit the spread. However, if the onset is slow and the effects are not unusual, significant spread may occur before the nature of the threat is realised.

    If the Mars life form has an unknown, fundamentally different biochemistry to life forms on Earth but nonetheless is able to cause adverse consequences in the Earth’s biosphere, this must be considered to be an extreme worst case scenario. If this were to be the case, a major rethink of the applicability of current strategies for dealing with pathogens would be required. Some of the questions that could arise include:

    • Can it be assumed that the consequences are limited to one or a few species?
    • Are currently available biocides effective?
    • How can the presence of the life form(s) be detected?
    • Susceptibility of population"

    They considered the extreme worst case scenario, where the Mars life form has an unknown, fundamentally different biochemistry to life forms on Earth but nonetheless is able to cause adverse consequences in the Earth’s biosphere. They identiried several factors that would need to be evaluated to help contain the hazard.

    * Can it be assumed that the consequences are limited to one or a few species?

    • Are currently available biocides effective?
    • How can the presence of the life form(s) be detected?
    • Susceptibility of population
  64. "5: "The Potential for Large-Scale Effects - 5.4 Being prepared"". Mars Sample Return backward contamination - strategic advice (PDF) (Report). European Science Foundation. 2012. It is critical that such strategies are designed to be implemented as soon as possible and at the local level and that they encompass:
    • observation of pre-defined indicators
    • rapid detection of anomalies
    • effective warning procedures
    • analysis, resistance and mitigation procedures
      horizontal tab character in |quote= at position 142 (help)
  65. Barry E. DiGregorio The dilemma of Mars sample return August 2001 Vol. 31, No. 8, pp 18–27..
  66. Quote to assist editors in verification from http://www.nap.edu/openbook.php?record_id=10138&page=60 :

    The preliminary examination, curation, and distribution for study of lunar samples from the LRL were generally successful. A community of outside investigators had been selected and funded by the time the Apollo 11 crew returned to Earth, and they had had some time to equip their laboratories and simulate analyses of lunar samples. Real lunar samples were distributed to them a few weeks after Apollo 11 (and subsequent missions) returned to Earth. The samples were allocated in a reasonably rational way, and with some exceptions they were protected from serious contamination.

    On the other hand, the quarantine program would have to be judged a failure. It greatly complicated sample processing, yet if lunar material had contained lethal microorganisms Earth would have been infected in two places: the Pacific Ocean, and Houston, Texas.

  67. 67.0 67.1 The Quarantine and Certification of Martian Samples National Academy Press (2002), Chapter 8, Conclusions and Recommendations (page 60)
  68. Nola Taylor Redd Curious About Life: Interview with Michael Meyer Astrobiology Magazine, 10/11/12
  69. Carl Sagan Cosmos Random House Publishing Group, 6 Jul 2011
  70. decisionresearch.org
  71. Donald MacGregor (Decision Research) Margaret S. Race, (SETI Institute) Microbiologists’ Perceptions of Planetary Protection
  72. To assist editors in verifying accuracy of the paraphrase This survey shows the diversity of views amongst microbiologists with a special interest in astrobiology, and so may help as background for the ESF comments about uncertainty of probability assessments. Caution, the respondents views were based on 1998 technology and science in a rapidly developing field. So is based on the biohazard containment capabilities, in situ analysis capabilities, and understanding of exobiology of the time. It is more useful as a way of indicating possibilities of a diversity of views, than as a direct indication of present day views amongst astrobiologists.
    • Asked if they thought there is life on Mars, 40.3% agreed and 32.3% said “don’t know".
    • Asked whether life on Mars could pose a biological threat to Earth, 42.8% said “don’t know.”, 34.4% disageed, and 22.9% agreed.
    • Asked about our ability to predict with reasonable certainty how life elsewhere would impact our environment, 71.2% disagreed and 10.4% said "I don't know".
    • Asked about various quarantine proposals, approximately half of respondents said that the (then) current proposed methods of quarantine of the samples are either moderately or highly adequate. About a third said “don’t know,”
    • Asked if materials returned to Earth from Mars should be considered hazardous until proven otherwise, all agreed except for 1.5% saying “don’t know,”
    • Asked about the potential for in situ experiments done on the Martian surface to sufficiently determine the safety of Mars samples; 58.2% disagreed, and 21.9% said "Don’t know.”
    The authors caution however

    "We have at present no evidence that life exists on other planets or bodies in our solar system, thus the cautious views expressed by respondents in the present study reflect the professional responsibility that most members of scientific groups would express when faced with a paucity of real data."

  73. 73.0 73.1 Wingspread Conference on the Precautionary Principle Wingspread, headquarters of Johnson Foundation, January 26, 1998
  74. Exploring the Origin, Extent, and Future of Life: Philosophical, Ethical and Theological Perspectives Chapter 10, A Christian Perspective, Cambridge University Press, 3 Sep 2009
  75. Cambridge project | The Cambridge Project for Existential Risk
  76. To assist editors in verifying accuracy of paraphrase

    ...The risk of back contamination is not zero. There is always some risk. In this case, the problem of risk - even extremely low risk - is exacerbated because the consequences of back contamination could be quite severe. Without being overly dramatic, the consequences might well include the extinction of species and the destruction of whole ecosystems. Humans could also be threatened with death or a significant decrease in life prospects

    In this situation, what is an ethically acceptable level of risk, even if it is quite low? This is not a technical question for scientists and engineers. Rather it is a moral question concerning accepting risk. Currently, the vast majority of the people exposed to this risk do not have a voice or vote in the decision to accept it. Most of the literature on back contamination is framed as a discourse amongst experts in planetary protection. Yet, as I've already argued, space exploration is inescapably a social endeavor done on behalf of the human race. Astronauts and all the supporting engineers and scientists work as representatives of all human persons....

  77. European Science Foundation - Mars Sample Return backward contamination - strategic advice July, 2012, ISBN 978-2-918428-67-1 - see 2. From remote exploration to returning samples. (for more details of the document see abstract )
  78. To assist editors in verifying validity of the paraphrase To quote from the ESF report "Through the study of a sample, researchers could make great progress in understanding the history of Mars, its volatiles and climate, its geological and geophysical history, and gain new insights into astrobiology. A Mars sample return has also been deemed an essential precursor to any human exploration missions to Mars Although some questions may be answered through in situ studies carried out by robotics on the Mars surface, returning a sample to Earth is desirable for several reasons:
    • Many experiments and their sample preparations will be too complex for an in situ robotic mission
    • Returning a sample allows for flexibility in dealing with the unknown and unexpected discoveries via new protocols, experiments and measurements
    • There are major limitations with regard to size and weight of instrumentation that can be flown
    • There is a significant communication delay to Mars, which impedes the ability to deal with emergencies
    • There is a much greater diversity in available instruments and an almost unlimited range of analytical techniques that can be applied on Earth
    • The ability to repeat experiments in multiple laboratories and confirm key results is available on Earth
    • Participation of entire analytical community is possible
    • There is the potential to propagate organisms if they are discovered
    In addition to the above points, returning a Mars sample will bring enormous public excitement and engagement to space-related activities, along with pride and prestige to this accomplishment of mankind."
  79. ICAMSR - Charter
  80. Included quote to assist editors in verification of the paraphrase

    In this White Paper we argue that it is not yet time to start down the MSR path. We have by no means exhausted our quiver of tools, and we do not yet know enough to intelligently select samples for return. In the best possible scenario, advanced instrumentation will identify biomarkers and define for us the nature of the sample to be returned. In the worst scenario, we will mortgage the exploration program to return an arbitrary sample that proves to be as ambiguous with respect to the search for life as ALH84001.



    ...We argue here that when in situ methods have definitively identified biomarkers, or when all reasonable in situ technologies have been exhausted, it will be time for MSR. We are not yet at that crossroad.

    ...Over the last decade the development of the Urey instrument for organic and oxidant detection on Mars has succeeded in addressing many of the aspects of primary concern for effective detection of biosignatures on Mars

  81. Requested by Dr. Michael A. Meyer, Discipline Scientist “An Exobiological Strategy for Mars Exploration” Prepared by the Exobiology Program Office, NASA HQ
  82. To assist editors in verification of my paraphrase

    Simply put, from a scientific and technological standpoint, we are not at Phase 4 yet. We don’t know where to go on Mars to get the samples we need to answer the life on Mars question, nor do we know how to design and build the vehicles and systems we need to accomplish a successful sample return mission, especially within the current resources of the Mars program...

    The notion that the next site we land at must necessarily be the site that we go to collect the first set of returned samples has got to be discouraged if we are ever going to explore the true diversity of the planet and its environmental history....

    There will always be scientists with laboratories who will advocate that NASA provide them with Mars samples for them to analyze. The fact is, however, that we don’t yet have the technology to do this within acceptable levels of cost and risk. As we are able to attract more resources to the program, it is vital that we use them to in manner which maximizes program’s excitement and further increases its scientific integrity...

  83. Life Marker Chip Robot Space Explorers, Open University
  84. 84.0 84.1 Planning for Mars Returned Sample Science: Final report of the MSR End-to End International Science Analysis Group
  85. Cranfield Health Detecting life on mars and the life marker chip: Antibody assays for detecting organic molecules in Liquid extracts of martian samples Phd thesis, Supervisor: Professor David C. Cullen, January 2012
  86. Gaskin, J.A.; Jerman, G.; Gregory, D.; Sampson, A.R., Miniature Variable Pressure Scanning Electron Microscope for in-situ imaging & chemical analysis Aerospace Conference, 2012 IEEE , vol., no., pp.1,10, 3–10 March 2012 doi: 10.1109/AERO.2012.6187064
  87. Mars Sample Return Mission? Naaah… Just Beam Back Martian DNA
  88. Biomedicine News Genome Hunters Go After Martian DNA
  89. A. D. Anbar1 and G. V. Levin A CHIRAL LABELED RELEASE INSTRUMENT FOR IN SITU DETECTION OF EXTANT LIFE., Concepts and Approaches for Mars Exploration (2012)
  90. Andrew D. Aubrey,1 John H. Chalmers, Jeffrey L. Bada, Frank J. Grunthaner, Xenia Amashukeli, Peter Willis, Alison M. Skelley, Richard A. Mathies, Richard C. Quinn, Aaron P. Zent, Pascale Ehrenfreund, Ron Amundson, Daniel P. Glavin, Oliver Botta, Laurence Barron,1 Diana L. Blaney, Benton C. Clark,11 Max Coleman, Beda A. Hofmann,12 Jean-Luc Josset,1 Petra Rettberg, Sally Ride, François Robert, Mark A. Sephton, and Albert Yen1 The Urey Instrument: An Advanced In Situ Organic and Oxidant Detector for Mars Exploration ASTROBIOLOGY Volume 8, Number 3, 2008
  91. J.L. Bada ·P. Ehrenfreund ·F. Grunthaner ·D. Blaney ·M. Coleman · A. Farrington ·A. Yen ·R. Mathies·R. Amudson ·R. Quinn ·A. Zent·S. Ride · L. Barron ·O. Botta ·B. Clark ·D. Glavin ·B. Hofmann · J.L. Josset·P. Rettberg · F. Robert ·M. Sephton Urey: Mars Organic and Oxidant Detector Space Sci Rev (2008) 135: 269–279
  92. Future Mars Missions: Can Humans Trump Robots?
  93. Dirk Schulze-Makuch A Bold New Chance for Mars Exploration! Blog for Huff Post Science, 05/11/2012
  94. Astrobiologist Proposes Fleet of Probes to Seek Life On Mars: Sensors Would Punch Into Soil, Run Range of Tests, Science Daily, Apr. 23, 2012
  95. Dirk Schulze-Makuch, James N. Head, Joop M. Houtkooper, Michael Knoblauch, Roberto Furfaro, Wolfgang Fink, Alberto G. Fairén, Hojatollah Vali, S. Kelly Sears, Mike Daly, David Deamer, Holger Schmidt, Aaron R. Hawkins, Henry J. Sun, Darlene S.S. Lim, James Dohm, Louis N. Irwin, Alfonso F. Davila, Abel Mendez, Dale Andersen Biological Oxidant and Life Detection (BOLD) mission: A proposal for a mission to Mars Planetary and Space Science, Volume 67, Issue 1, July 2012, Pages 57-69, ISSN 0032-0633, http://dx.doi.org/10.1016/j.pss.2012.03.008.
  96. Jeff Foust A curious future for Mars exploration thespacereview.com, Monday, August 13, 2012
  97. Robert Zubrin Mars the Hard Way Space News, Dec. 3, 2012
  98. To assist editors in verification of paraphrase of Zubrin's views from: A curious future for Mars exploration

    I believe the program has become overfocused on sample return,” Zubrin said. While he supported robotic exploration for Mars as a step towards human missions, he worried that trying to land on Mars, collect samples, place them into a rocket that launches them into Mars orbit for later retrieval and return to Earth may be too complex. “I think that extrapolating the robotic program to sample return is taking it beyond when it beneficially trades off against human exploration,” he said.



    “I do not see how sample return, as such, is vital for human exploration, and I think that saying that it is actually creates an obstacle to human exploration,” Zubrin said. Zubrin instead supports an “aggressive” program of rover missions, based on the highly-successful MERs. “Here we have a very successful system, why don’t we churn these things out, start sending two of them every two years to Mars, different locations with different instruments, conducing different kinds of investigations, make them into a workhorse,” he said. Doing so, he said, could reduce the cost of each mission to $200–400 million, far less than the estimated $2.5 billion cost of Curiosity.

    Then, writing an article himself in Space News in Dec. 3, 2012, he says as additional motivation for his approach, that humans post colonization of Mars can do far better sample return missions than a robotic mission can do now: from: Mars the Hard Way Space News, Dec. 3, 2012

    It is certainly possible to propose alternative robotic mission sets consisting of assortments of orbiters, rovers, aircraft, surface networks, etc., that might produce a greater science return than the Mars sample return mission, much sooner, especially in view of the fact that human explorers could return hundreds of times the amount of samples, selected far more wisely, from thousands of times the candidate rocks, than a sample return mission.

  99. Safe methods for MSR
  100. 100.0 100.1 100.2 The Human Exploration of Space, By Committee on Human Exploration, National Research Council, 1997
  101. Richard S. Johnston John A. Mason Bennie C. Wooley, Ph.D.[*] Gary W. McCollum Bernard J. Mieszkuc BIOMEDICAL RESULTS OF APOLLO, SECTION V, CHAPTER 1, THE LUNAR QUARANTINE PROGRAM Lyndon B. Johnson Space Center
  102. Carl Sagan,The Cosmic Connection - an Extraterrestrial Perspective (1973) ISBN 0521783038

    It is no use arguing that samples can be brought back safely to Earth, or to a base on the Moon, and thereby not be exposed to Earth. The lunar base will be shuttling passengers back and forth to Earth; so will a large Earth orbital station. The one clear lesson that emerged from our experience in attempting to isolate Apollo-returned lunar samples is that mission controllers are unwilling to risk the certain discomfort of an astronaut – never mind his death – against the remote possibility of a global pandemic. When Apollo 11, the first successful manned lunar lander, returned to Earth – it was a spaceworthy, but not a very seaworthy, vessel – the agreed-upon quarantine protocol was immediately breached. It was adjudged better to open the Apollo 11 hatch to the air of the Pacific Ocean and, for all we then knew, expose the Earth to lunar pathogens, than to risk three seasick astronauts. So little concern was paid to quarantine that the aircraft-carrier crane scheduled to lift the command module unopened out of the Pacific was discovered at the last moment to be unsafe. Exit from Apollo 11 was required in the open sea.

  103. For editor verification of the paraphrase

    Using the return flight as an incubation period and the crew as guinea pigs (as has been suggested) is not a solution to back contamination on human missions. Would the whole mission be risked if an unanticipated contamination occurred? How would the cause of the infection be known with enough certainty to justify destroying the returning spacecraft before it entered Earth's atmosphere? The whole spacecraft, not only the astronauts, would be contaminated. In addition infection might not be the only risk. A returning organism could possibly cause some long-term changes in our environment, perhaps remaining undetected for a while. Although such an event may be judged to have a very low probability, a convincing case that prudence has been exercised will have to be made to the public. (Page 30)

  104. Mars - A Warmer, Wetter Planet. Springer. 2004. p. 440. What if the astronauts should fall ill on the return journey? How would we quarantine them? On a space station? Space stations eventually return to Earth; until they crash, they must be resupplied. Quarantine at a moon base? That would be expensive and requires resupply. Would it be a lifetime quarantine? How could anybody deal with that? The most effective and practical lifetime quarantine would be on Mars, where the astronauts, by design, could raise families and build an infrastructure. The astronauts would venture forth from Earth much a Europeans and Polynesians of the last two milenia ventured across the seas, knowing that return was unlikely. Hopefully and most likely, fears of a Martian Andromeda Strain will not be realised. 
  105. 105.0 105.1 LOW-LATENCY TELEROBOTICS FROM MARS ORBIT: THE CASE FOR SYNERGY BETWEEN SCIENCE AND HUMAN EXPLORATION, Concepts and Approaches for Mars Exploration (2012)
  106. Space Exploration Enabled by Telepresence: Combining Science and Human Exploration Based on Findings from: “Exploration Telerobotics Symposium” May 2-3, 2012 NASA Goddard Space Flight Center]
  107. Space Exploration Via Telepresence: The Case for Synergy Between Science and Human Exploration, Findings and Observations from: “Exploration Telerobotics Symposium” May 2-3, 2012 NASA Goddard Space Flight Center
  108. Decadal Survey Video - see 36.00 - and 48.30 for the main Mars sample return sections
  109. Decadal Survery Executive Summary
  110. To assist editors with verification Some quotes from the survey report follow to show how highly the mission was valued in the survey:

    "A major accomplishment of the committee’s recommended program will be taking the first

    critical steps toward returning carefully selected samples from the surface of Mars. Mars is unique among the planets in having experienced processes comparable to those on Earth during its formation and evolution. Crucially, the martian surface preserves a record of earliest solar system history, on a planet with conditions that may have been similar to those on Earth when life emerged. It is now possible to select a site on Mars from which to collect samples that will address the question of whether the planet was ever an abode of life. The rocks from Mars that we have on Earth in the form of meteorites cannot provide an answer to this question. They are igneous rocks, whereas recent spacecraft observations have shown the occurrence on Mars of chemical sedimentary rocks of aqueous origin, and rocks that have been aqueously altered. It is these materials, none of which are found in meteorites, that provide the opportunity to study aqueous environments, potential prebiotic chemistry, and perhaps, the remains of early martian life."

    During the decade of 2013-2022, NASA should establish an aggressive, focused technology development and validation initiative to provide the capabilities required to complete the challenging MSR campaign

    Finally, searching for evidence of extant life at Mars with a limited suite of experiments, compounded by the uncertainty regarding the nature of possible martian life and issues of terrestrial contamination, would be difficult and carries very high scientific risk

    Experience based on previous studies (e.g., of meteorites, the Moon, cometary dust, and the solar wind) strongly supports the importance of sample analysis. Such a diversity of techniques, analysis over time, improvements in sensitivity, and new approaches available in terrestrial labs are expected to revolutionize our understanding of Mars in ways that simply cannot be done in situ or by remote sensing.

  111. Summary of the Final Report Mars Program Planning Group, 25 September 2012 MPPG
  112. Mars Sample Recovery & Quarantine (1985) DAVID S. F. PORTREE 02.14.13

[This is the original article I wrote for Wikipedia before it was merged away]

This article uses material from the June 2013 revision of Concerns for an early Mars sample return on Wikipedia ( view authors). License under CC BY-SA 3.0. Wikipedia logo