Difference between revisions of "Environmental conditions"
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The Martian [[atmosphere]] has one hundredth of Earth's atmospheric density and seven thousandths of Earth's atmospheric pressure. The pressure varies considerably from day to day, from season to season, and from place to place on Mars. For practical purposes when designing pressure vessels to maintain life supporting conditions on Mars it is sufficient to estimate the Martian atmospheric pressure as zero. | The Martian [[atmosphere]] has one hundredth of Earth's atmospheric density and seven thousandths of Earth's atmospheric pressure. The pressure varies considerably from day to day, from season to season, and from place to place on Mars. For practical purposes when designing pressure vessels to maintain life supporting conditions on Mars it is sufficient to estimate the Martian atmospheric pressure as zero. | ||
| − | == Wind == | + | ==Wind== |
High wind speeds can occur in large-scale [[Dust storms|storms]] or small [[dust devils]]. There is evidence that wind speeds can exceed 50 meters/second (111 miles/hour). However, the thin atmosphere means that the pressure created by wind is weaker by a factor of 9 than it would be at the same wind speed on Earth. Generally high winds will probably not be a threat to human explorers, with the possible exception of areas where the ground slopes steeply.<ref name=":0">National Research Council. 2002. ''Safe on Mars: Precursor Measurements Necessary to Support Human Operations on the Martian Surface''. Washington, DC: The National Academies Press. <nowiki>https://doi.org/10.17226/10360</nowiki>.</ref> | High wind speeds can occur in large-scale [[Dust storms|storms]] or small [[dust devils]]. There is evidence that wind speeds can exceed 50 meters/second (111 miles/hour). However, the thin atmosphere means that the pressure created by wind is weaker by a factor of 9 than it would be at the same wind speed on Earth. Generally high winds will probably not be a threat to human explorers, with the possible exception of areas where the ground slopes steeply.<ref name=":0">National Research Council. 2002. ''Safe on Mars: Precursor Measurements Necessary to Support Human Operations on the Martian Surface''. Washington, DC: The National Academies Press. <nowiki>https://doi.org/10.17226/10360</nowiki>.</ref> | ||
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*[[Dust devils]]: ? | *[[Dust devils]]: ? | ||
| − | == Dust == | + | ==Dust== |
Airborne dust presents potential problems for human explorers. Dust could wear on moving parts if it infiltrates machinery, or could wear away EVA suit seals. Dust that enters a habitat after an EVA could clog air filters. It could accumulate on solar panels, antennas, optical sensors, thermal radiators, or EVA suit visors. The electric charge generated by rover wheels could cause dust adherence that interferes with the drive train.<ref name=":0" /> | Airborne dust presents potential problems for human explorers. Dust could wear on moving parts if it infiltrates machinery, or could wear away EVA suit seals. Dust that enters a habitat after an EVA could clog air filters. It could accumulate on solar panels, antennas, optical sensors, thermal radiators, or EVA suit visors. The electric charge generated by rover wheels could cause dust adherence that interferes with the drive train.<ref name=":0" /> | ||
| − | == Electrostatic Charging == | + | ==Electrostatic Charging== |
Human explorers may need to deal with electrostatic shock hazards. On Earth, soil contains enough moisture to conduct electricity, which means electric charge will not build up in grounded objects. Not enough liquid water is present for this effect to occur on Mars. The discharge of built-up static electricity might damage electronics. Equipment and procedures will need to be designed to account for this hazard. Some methods to overcome this sort of problem have been devised at a research station in Antarctica, where the ground contains ice but not liquid (conductive) water.<ref name=":0" /> | Human explorers may need to deal with electrostatic shock hazards. On Earth, soil contains enough moisture to conduct electricity, which means electric charge will not build up in grounded objects. Not enough liquid water is present for this effect to occur on Mars. The discharge of built-up static electricity might damage electronics. Equipment and procedures will need to be designed to account for this hazard. Some methods to overcome this sort of problem have been devised at a research station in Antarctica, where the ground contains ice but not liquid (conductive) water.<ref name=":0" /> | ||
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*[http://www.nasa.gov/worldbook/mars_worldbook.html Nasa: World Book] | *[http://www.nasa.gov/worldbook/mars_worldbook.html Nasa: World Book] | ||
*[http://kids.earth.nasa.gov/archive/air_pressure/index.html Nasa: Atmospheric Pressure] | *[http://kids.earth.nasa.gov/archive/air_pressure/index.html Nasa: Atmospheric Pressure] | ||
| + | *Beaty, DW, et al. 2005. [https://mepag.jpl.nasa.gov/reports/MHP_SSG_(06-02-05).pdf An Analysis of the Precursor Measurements of Mars Needed to Reduce the Risk of the First Human Mission to Mars.] | ||
| + | == References == | ||
[[Category:Atmospheric Sciences]] | [[Category:Atmospheric Sciences]] | ||
| + | <references /> | ||
Revision as of 10:50, 29 September 2019
The Environmental conditions on Mars are different from those of Earth. Human beings can not live there without technical systems. Unless successful terraforming can be performed, Martian settlers are bound to artificial habitats.
Contents
Temperature
The temperatures on the Martian surface is much lower than on Earth.
- Average atmosphere temperature: -63 °C
- Diurnal temperature range: -89 °C to -31 °C (Viking 1 Lander site)
- Minimum: −125 °C near the poles in winter
- Maximum: 20 °C near the equator
Atmosphere pressure
The Martian atmosphere has one hundredth of Earth's atmospheric density and seven thousandths of Earth's atmospheric pressure. The pressure varies considerably from day to day, from season to season, and from place to place on Mars. For practical purposes when designing pressure vessels to maintain life supporting conditions on Mars it is sufficient to estimate the Martian atmospheric pressure as zero.
Wind
High wind speeds can occur in large-scale storms or small dust devils. There is evidence that wind speeds can exceed 50 meters/second (111 miles/hour). However, the thin atmosphere means that the pressure created by wind is weaker by a factor of 9 than it would be at the same wind speed on Earth. Generally high winds will probably not be a threat to human explorers, with the possible exception of areas where the ground slopes steeply.[1]
Wind speed (Viking Lander sites)
- Summer: 2-7 m/s
- Fall: 5-10 m/s
- Dust storms: 17-30 m/s
- Dust devils: ?
Dust
Airborne dust presents potential problems for human explorers. Dust could wear on moving parts if it infiltrates machinery, or could wear away EVA suit seals. Dust that enters a habitat after an EVA could clog air filters. It could accumulate on solar panels, antennas, optical sensors, thermal radiators, or EVA suit visors. The electric charge generated by rover wheels could cause dust adherence that interferes with the drive train.[1]
Electrostatic Charging
Human explorers may need to deal with electrostatic shock hazards. On Earth, soil contains enough moisture to conduct electricity, which means electric charge will not build up in grounded objects. Not enough liquid water is present for this effect to occur on Mars. The discharge of built-up static electricity might damage electronics. Equipment and procedures will need to be designed to account for this hazard. Some methods to overcome this sort of problem have been devised at a research station in Antarctica, where the ground contains ice but not liquid (conductive) water.[1]
Open issues
- Is there a potential threat from dust devils?
External Links
- Nasa: Mars Fact Sheet
- Nasa: World Book
- Nasa: Atmospheric Pressure
- Beaty, DW, et al. 2005. An Analysis of the Precursor Measurements of Mars Needed to Reduce the Risk of the First Human Mission to Mars.
