could be more underground ice on Mars than previously thought, and large parts of it may be just south of Ecuador.
In fact, one of the proposed landing sites for Mars Science Laboratory (MSL) is the mother lode that could attract scientific perspectives. The comments of two spacecraft, the Mars Reconnaissance Orbiter (MRO) and Mars Express have revealed potential deposits ice under the surface in areas south of Ecuador, including one near the Holden crater , with estimated reserves of water ice beneath the surface of about 50 to 500 kg / m2 only two or three meters below the surface. This is the first evidence of ice-latitude "tropical" on Mars as low as 25 degrees.
In 2009, the MRO observations revealed water ice as low as 45 degrees North in a small recent impact crater and the permanent water ice at the poles of Mars are known to exist. But most robotic missions (and hopefully one day human missions) need to sit closer to Ecuador to meet the criteria safety and engineering constraints. As proof, the four proposed sites for the MSL landing which hover within 25 degrees of Ecuador.
Of course, not underground ice on Mars can be seen directly, but certain surface characteristics and thermal properties create the potential for subsurface ice. The OMEGA (Observatoire pour la Mineralogy, l'Eau, les Glaces et l'Activité) on board the Mars Express and CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) onboard the Mars Reconnaissance Orbiter imaging spectrometers used in near infrared to measure solar radiation scattered by the surface, providing spectral imaging that have been used to assess the composition of minerals and condensed on the surface of Mars.
What led scientists to this area? The answer is that surface distributions were observed seasonal CO2 frost on the slopes facing the pole, the carbon dioxide ice usually forms only on the surface, if a cold layer below, which can come from water ice or bedrock.
color image of the crater region Holden.Credito: NASA / JPL / University of Arizona.
But in this case, Mathieu Vincendon and his team at Brown University concluded that the base rocks could not be responsible for creating the observed thermal properties which stores and releases heat from two or three feet below the surface. Evidence of a uniform layer of rock that runs along the equatorial region, has never been seen in orbital images, which would have been revealed by the processes of erosion or impact.
"scenarios using different models within the range of uncertainties leads to the result that water ice is present at one meter from the surface in all of the 20-30 ° slopes facing the pole fall to about 25 ° S, "the team writes in the article. "The relevant thermal depths proved to be 2 or 3 metros.Por therefore, a rich thick layer of ice is implicit, which leads to a perennial reservoir of water ice beneath the surface estimated at about 50 -500 kg / m2 on steep slopes.
The team believes that the subsurface ice may be possible remains of the last ice age on Mars, and could provide water which will be needed for future exploration of Mars. More thermal measurements of seasonal variations in temperature could help get more accurate depths of permafrost.
Holden crater is at the edge of the area which is located in the water ice below the surface at 26 ° S
read the study HERE
source of information:
http://www.universetoday.com/83840/vast-areas-of-low-latitude-subsurface-ice -found-on-mars /
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