Lichens, cyanobacteria and molds growing in humidity of simulated Martian atmosphere: Difference between revisions
Jump to navigation
Jump to search
Lichens, cyanobacteria and molds growing in humidity of simulated Martian atmosphere (edit)
Revision as of 02:25, 23 September 2018
, 5 years ago→Humidity observations of the Mars atmosphere by Curiosity
Line 5:
[[Image:Curiosity humidity measurements.gif|thumb|Upper chart shows the humidity, lower chart shows the volume mixing ratio in parts per million, both measurements taken at the same time, height 1.6 meters above the ground]][[Image:Curiosity temperature measurements.gif|thumb|Upper chart shows the average temperature, lower chart shows the range, the warm orange and red colours are Curiosity annual readings, the blue and green dcolours are for the Viking landers and the gray colours are for the Phoenix lander]]
This section is based on the survey article by Martinez et al, "The modern near-surface martian climate: A review of in-situ meteorological data from Viking to Curiosity."<ref>Martínez, G. M., C. N. Newman, A. De Vicente-Retortillo, E. Fischer, N. O. Renno, M. I. Richardson, A. G. Fairén et al. "The modern near-surface martian climate: A review of in-situ meteorological data from Viking to Curiosity." Space Science Reviews 212, no. 1-2 (2017): 295-338.</ref>
The humidity variations on Mars are mainly due to the daily and seasonal variations of temperature of the air. Colder air has a higher relative humidity for the same water content.
The amount of water vapour can be measured as the volume mixing ratio of water vapour (VMR). This varies between around 10 ppm in winter and 70 ppm in summer at the Curiosity site. You might expect the highest relative humidithy then to be in summer, but no, it's in winter, because it is so much colder then. The summer relative himidity is about 10% and the winter relative humidity around 70%. It's rather easy to remember, by coincidence. 10ppm for 70% RH and 70 ppm for 10% RH.
Curiosity has measured relative humidity readings of up to 70% in winter, measured at a height of 1.6 meters above ground level (see Sect 14<ref>[https://link.springer.com/article/10.1007/s11214-017-0360-x#Sec14 Sec 14]</ref>. This is in winter with a temperature range of around 50 C and mean temperature around -63 C, so lowest temperature around -88 C (see their figure 5<ref>[https://link.springer.com/article/10.1007/s11214-017-0360-x#Fig5 Fig5]</ref>), and the highest humidity is normally reached between 04:00 and 06:00 Local Mean Solar Time (LMST).. The lowest humidity readings are between 10:00 and 18:000 LMST, when they are typically less than 5%
| |||
