Environmental conditions - Revision history

Michel Lamontagne: /* Atmosphere pressure */

2023-04-26T19:09:48Z

Atmosphere pressure

Michel Lamontagne: /* External Links */

2022-01-18T14:51:47Z

External Links

Michel Lamontagne: /* Open issues */

2022-01-18T14:51:00Z

Open issues

RichardWSmith: Added wind speed in Dust devils

2021-04-01T00:42:02Z

Added wind speed in Dust devils

RichardWSmith: Noted that Martian dust is somewhat toxic.

2021-03-29T20:01:29Z

Noted that Martian dust is somewhat toxic.

JimL: Added an external link.

2019-09-29T17:50:13Z

Added an external link.

JimL: Added some information on physical hazards from the NAP report Safe on Mars.

2019-01-31T00:08:07Z

Added some information on physical hazards from the NAP report Safe on Mars.

Jburk at 22:52, 17 December 2018

2018-12-17T22:52:39Z

Rfc: image added

2018-02-13T19:17:48Z

image added

Farred: /* Atmosphere pressure */

2010-02-22T10:49:08Z

Atmosphere pressure

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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.
-Note that during the southern winter, a significant fraction of the worlds carbon dioxide atmosphere freezes out as dry ice.  This [[Sublimation|Sublimates]] back to gas in the southern summer. Thus there is a slow varying of air pressure thruout the Martian year.
+Note that during the southern winter, a significant fraction of the planet's carbon dioxide atmosphere freezes out as dry ice.  This [[Sublimation|Sublimates]] back to gas in the southern summer. Thus there is a slow varying of air pressure throughout the Martian year.
 ==Wind==

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 ==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" />
 ==External Links==

@@ Line 32: / Line 32: @@
 ==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" />
 ==External Links==

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 *Fall: 5-10 m/s
 *[[Dust storms]]: 17-30 m/s
-*[[Dust devils]]: ?
+*[[Dust devils]]: Typically 10 m/s, max speed at Viking landers estimated at 46m/s.
 ==Dust==

@@ Line 12: / Line 12: @@
 ==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==
@@ Line 24: / Line 26: @@
 ==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" />  Also note that the Martian dust is composed of 'fines', very small particles.  This will be especially stressful on moving parts.
 ==Electrostatic Charging==
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 *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 ==
+==References==
 [[Category:Atmospheric Sciences]]
 <references />

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 ==Atmosphere pressure==
-The Martian [[atmosphere]] has one hundreth 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 speed (Viking Lander sites)==
+== Wind ==
-*Summer: 2-7 m/s
+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>
 *Fall: 5-10 m/s
 *[[Dust storms]]: 17-30 m/s
 *[[Dust devils]]: ?
 ==Open issues==
 * Is there a potential threat from dust devils?
 ==External Links==
 *[http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html Nasa: Mars Fact Sheet]
 *[http://www.nasa.gov/worldbook/mars_worldbook.html Nasa: World Book]

← Older revision		Revision as of 22:52, 17 December 2018
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	*[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]

−	[[Category:~~Climate~~]]	+	[[Category:Atmospheric Sciences]]

← Older revision		Revision as of 19:17, 13 February 2018
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		+	[[Image:126609main_image_feature_400a_ys_full.jpg\|thumb\|right\|300px\|The dry and cold surface]]
	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 [[habitat]]s.		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 [[habitat]]s.