Evidence of water on Mars found by Mars Reconnaissance Orbiter
[9][10][11] In a study published in Icarus in 2016, A team, headed by David Stillman, identified 239 locations for recurring slope lineae within Valles Marineris.
An analysis of data from the Mars Odyssey Neutron Spectrometer revealed that the RSL sites do not contain any more water than found at anywhere else at similar latitudes.
[13] A study published in Nature Geoscience, suggest that very little water is involved in creating recurrent slope lineae because these streaks only occur on steep slopes—slopes that would allow dry sand and dust to move down.
[27][28][29] The earliest evidence of life on Earth appear in seafloor deposits that are similar to those found in the Eridania basin.
[31] Research, in the January 2010 issue of Icarus, described strong evidence for sustained precipitation in the area around Valles Marineris.
The inverted former stream channels may be caused by the deposition of large rocks or due to cementation of loose materials.
[34] In an article published in January 2010, a large group of scientists endorsed the idea of searching for life in Miyamoto Crater because of inverted stream channels and minerals that indicated the past presence of water.
[40][41] Scientists are excited about finding hydrated minerals such as sulfates and clays on Mars because they are usually formed in the presence of water.
[43] More research using data collected by the SHARAD (SHAllow RAdar Detector) on the MRO has found layers of ice-water interspersed with dirt at the northern pole under the Planum Boreum.
, Changes in Mars's orbit and tilt cause significant changes in the distribution of water ice from polar regions down to latitudes equivalent to Texas.
The water returns to the ground at lower latitudes as deposits of frost or snow mixed generously with dust.
Some repeat observations of gullies have displayed changes that some scientists argue were caused by liquid water over the period of just a few years.
Observations over the past few years support a model in which currently active gully formation is driven mainly by seasonal CO2 frost.
[58] Simulations described in a 2015 conference, show that high pressure CO2 gas trapping in the subsurface can cause debris flows.
When the higher intensity sunlight of spring begins, light penetrates the translucent dry ice layer, consequently warming the ground.
The dirt particles mix with the pressurized gas and act as a fluid that can flow down the slope and carve gullies.
Glaciers, loosely defined as patches of currently or recently flowing ice, are thought to be present across large but restricted areas of the modern Martian surface, and are inferred to have been more widely distributed at times in the past.
[73] A variety of surface textures seen in imagery of the midlatitudes and polar regions are also thought to be linked to sublimation of glacial ice.
Another major advantage of these glacial landscapes over other sources of Martian water is that they can easily detected and mapped from orbit.
Lobate debris aprons are shown below from the Phlegra Montes, which are at latitude of 38.2 degrees north, so the discovery of water ice in LDAs greatly expands the range of easily available on Mars.
[65][page needed] Tongue-shaped glaciers Other ice-related features Huge, easy to get to, deposits of ice were found by a team of researchers using instruments on board the Mars Reconnaissance Orbiter (MRO).
The scientists found eight eroding slopes showing exposed water ice sheets as thick as 100 meters.
[80][81][82] Shane Byrne of the University of Arizona Lunar and Planetary Laboratory, Tucson, one of the co-authors remarked that future colonists of the Red Planet would be able to gather up ice with just a bucket and shovel.
[84] Also, Thermal Emission Imaging System (THEMIS) measurements show a temperature in the late-afternoon that is above the frost point.
[82] "There is shallow ground ice under roughly a third of the Martian surface," said the study's lead author, Colin Dundas of the U.S. Geological Survey's Astrogeology Science Center in Flagstaff, Arizona. "
Scalloped depressions are thought to form from the removal of subsurface material, possibly interstitial ice, by sublimation.
[90] Research, reported in the journal Science in September 2009,[91] demonstrated that some new craters on Mars show exposed, pure, water ice.
The ice was confirmed with the Compact Imaging Spectrometer (CRISM) on board the Mars Reconnaissance Orbiter (MRO).
[100] Furthermore, chemical data from the Compact Reconnaissance Imaging Spectrometer orbiting the planet have shown water related mineral forms: opal (hydrated silica) and iron sulfates.
These features of light-toned layered deposits strongly suggest that there was long lasting precipitation and surface runoff during the Hesperian epoch of Martian history.
