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Mars has a reasonably well studied climate, starting in earnest with the Viking program in 1975 and continuing with such probes as the highly successful Mars Global Surveyor. This work has been developed along side a scientific computer simulation called the Mars General Circulation Model [1]. NASAs Viking program consisted of two unmanned space missions to Mars, Viking 1 and Viking 2. ...
Artists conception of Mars Global Surveyor (NASA) The Mars Global Surveyor (MGS) is a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ...
Low atmospheric pressure
 2001 Hellas Basin dust storm The martian atmosphere, which is composed mainly of carbon dioxide has a surface pressure of about 6 millibars, much lower than the Earths 1013 millibars. One effect of this is that Mars' atmosphere can react much more quickly to a given energy input than can our atmosphere [2]. As a consequence Mars is subject to strong thermal tides, similar to the sea tides on Earth, but produced by solar heating rather than a gravitational effect. These tides can be significant, being up to 10% of the total atmosphereic pressure. Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ...
Surface pressure is the atmospheric pressure at a point of Earths surface. ...
A millibar (mb) is 1/1000th of a bar, a unit for measurement of pressure. ...
Although the temperature on Mars can reach above 273K (0°C), liquid water is unstable due to the low atmospheric pressure, and water ice simply sublimes into water vapour. An exception to this is in the Hellas Planitia impact crater, the largest such crater on Mars. It is so deep that the atmospheric pressure at the bottom reaches 11.55 millibars, which is abaove the triple point of water, so if the temperature exceeds 0°C liquid water can exist here. NASA image of Hellas Planitia Hellas Planitia, also known as the Hellas Impact Basin, is a roughly circular impact crater located in the southern hemisphere of the planet Mars. ...
The surface of Mars has a very low thermal inertia, which means it will heat up fast when the sun shines on it. Typical daily temperature swings, away from the polar regions, are around 100K. On Earth winds often develop in areas where thermal inertia changes suddenly, such as from sea to land. There are no seas on Mars, but therre are areas where the thermal inertia of the soil changes, leading to morning and evening winds akin to the sea breazes on Earth[1]. Volumetric heat capacity (VHC) describes the ability of a given volume of a substance to store heat while undergoing a given temperature change, but without undergoing a phase change. ...
Effect of dust storms  Hubble, Colossal Polar Cyclone on Mars When the Mariner 9 probe arrived at Mars in 1979 the world expected to see crisp new pictures of surface detail, instead they saw a near planet wide dust storm[2] with only the giant volcano Olympus Mons showing above the haze. The storm lasted for a month, an occurrence scientists have since learned in quite common on Mars. On June 26, 2001, the Hubble Space Telescope spotted a dust storm brewing in Hellas Basin on Mars. A day later the storm "exploded" and became a global event. This dust storm raised the temperature of the atmosphere of Mars by 30 degrees C. Mariner 9 launch Mariner 9 was a NASA space probe orbiter that helped in the exploration of Mars and was part of the Mariner program. ...
Note: This article contains special characters. ...
Olympus Mons Olympus Mons (Latin, Mount Olympus) is the tallest known mountain in our solar system, located on the planet Mars at approximately . ...
NASA image of Hellas Planitia Hellas Planitia, also known as the Hellas Impact Basin, is a roughly circular impact crater located in the southern hemisphere of the planet Mars. ...
A consequence on the low surface pressure on Mars, storms need winds of 40 to 50mph before dust is lifed into the atmosphere. Dust storms are common during perihelion, when the planet receives 40 percent more sunlight than during aphelion (when Mars is farthest from the Sun). During aphelion water ice clouds form in the atmosphere, interacting with the dust particles in affecting the temperature of the planet[3]. This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
It has been suggested that dust storms on Mars could play a role in storm formation similar to that of water clouds on earth.[citation needed]
Dry ice polar caps The polar regions of Mars are cold enough for cabon dioxide to condense and form polar ice caps. So much of the atmosphere can condense at the poles in summer and winter that the atmospheric pressure can vaty bu up to a third of its mean value of 6 millibars. The eccentricity of Mars' orbit affect this cycle, as well as other factors. In the spring and autumn wind caused by this sublimation process is so strong that it can be a cause of the global dust storms mentioned above[4].
Seasons The eccentricity of Mars' orbit is 0.1, much greater than the Earths, so the variation in insolation on Mars is greater as the planet passes round the Sun (the martian year lasts 687 days, roughly 2 Earth years). Mars' obliquity dominates the seasons however, just as on earth, but precession in the allignment of the obliquity and eccentricity lead to global warming and cooling ('great' summers and winters) with a period of 170,000 years[5]. Look up Eccentricity in Wiktionary, the free dictionary. ...
TOA and surface insolation, annual mean Insolation is the incoming solar radiation that reaches a planet and its atmosphere or, by extension, any object exposed to solar rays, such as watts per square meter of Sun-facing cross section, across the entire electromagnetic spectrum; most of that power is in...
Axial tilt is an astronomical term regarding the inclination angle of a planets rotational axis in relation to its orbital plane. ...
Precession refers to a change in the direction of the axis of a rotating object. ...
Evidence for recent climatic change  Pits in south polar ice cap, MGS 1999, NASA In 1999 the Mars Global Surveyor photographed pits in the layer of frozen carbon dioxide an the martian south pole, because of their striking shape and orientation these pits have become known as swiss cheese features. In 2001 it photographed the same pits again and found that they had grown slightly larger [3]. Artists conception of Mars Global Surveyor (NASA) The Mars Global Surveyor (MGS) is a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ...
More recent observations indicate that Mars' south pole is continuing to melt. "It's evaporating right now at a prodigious rate," says Michael Malin, principal investigator for the Mars Orbiter Camera (MOC) [4]. The pits in the ice are growing by about 3 meters a year, at that rate it will be thousands of years till it is all gone. Malin states that conditions on Mars are not currently conductive to the formation of new ice. Michael C. Malin (born 1950) is an American astronomer, space-scientist, and CEO of Malin Space Science Systems. ...
Calculations with the Mars General Circulation Model show that the local climate around the martian south pole is currently in an unstable period - an instability that finds its roots in the geography of the region, leading Colaprete et al. to speculate that the melting of the polar ice is a local phenomenon rather than a global one[6].
See also Mars Climate Orbiter during tests The Mars Climate Orbiter (formerly the Mars Surveyor 98 Orbiter) was one of two spacecraft in the Mars Surveyor 98 program, the other being the Mars Polar Lander (formerly the Mars Surveyor 98 Lander). ...
Planum Australe, taken by Mars Global Surveyor. ...
Viking mosaic of Planum Boreale and surrounds. ...
Michael C. Malin (born 1950) is an American astronomer, space-scientist, and CEO of Malin Space Science Systems. ...
References - ^ NASA. Mars General Circulation Modeling. NASA. Retrieved on 2007-02-22.
- ^ MGCM. Mars' low surface pressure.... NASA. Retrieved on 2007-02-22.
- ^ MOC Observes Changes in the South Polar Cap. Malin Space Science Systems. Retrieved on 2007-02-22.
- ^ Evaporating ice. Astronomy.com. Retrieved on 2007-02-22.
2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ...
February 22 is the 53rd day of the year in the Gregorian Calendar. ...
2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ...
February 22 is the 53rd day of the year in the Gregorian Calendar. ...
2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ...
February 22 is the 53rd day of the year in the Gregorian Calendar. ...
2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ...
February 22 is the 53rd day of the year in the Gregorian Calendar. ...
External Links - Mars Today, current conditions on Mars.
- Nature study explains mystery of Mars icecaps.
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