The MRO spacecraft orbiting Mars since 2005 has taught us new things about the most studied planet in the solar system
Volcanic activity
A basin recently named Eden Patera has raised many questions as to its origin. Among the researchers there were those who think that it was created due to an asteroid impact, others think that it is the remains of a massive volcano. According to this approach what you see is actually the caldera of a volcano. The researchers think that a large amount of gas burst out through the crust to the surface quickly (1). In Athabasca Valles, which is near the equator, and in Cerberus Palus, both parts of Elysium, lava was found in the configuration of spiral coils (spiral coils) like on the big island of Hawaii and on the Galapagos reef, which are between 5 and 30 meters wide. They are larger than those found on Earth. They were probably formed when the lava flows moved over each other at different speeds or in different directions. By 2012, there were close to 200 such formations in Cerberus Palus (2).
Makhteshim
Until 2012, over 635,000 impact craters with a diameter of more than a kilometer (3) were counted on Mars. Argyre Crater is oversized. It is 1,800 km in diameter and 5 km deep and was created by an asteroid impact, and changes occurred due to wind erosion and the flow of water and ice. For this reason the surface around the crater Hooke has a rounded shape found inside it. The diameter of this crater is 138 km and its depth is 2.5 km. Perpetual winds created dunes in it and yardangs are found in its south. The thing that stands out in the photographs of the crater is a layer of CO2 that extends along the southern part of the crater (4). In a photograph taken on May 19, 2010, a crater was observed that was not seen in previous observations in March 2008. The location is 63.9 degrees north 44.9 degrees east (5).
dunes
Many photographs show sand dunes and ripples (ripples - movement of sand grains that create wave-like lines on the surface of the dune) moving a few meters along the surface in dozens of places. It was a surprise that was not expected at all. The reason for this was based on the assessment that the grains of sand were too heavy and therefore remained in place. In an experiment conducted in a wind tunnel that simulated the conditions on Mars, it became clear that winds moving at a speed exceeding 130 km/h are able to transport grains of sand, while on Earth a speed of 16 km/h is sufficient. The first evidence of dune movement was observed between 1997 and 2006 by the Mars Global Surveyor spacecraft cameras, but the resolutions of the spacecraft cameras were not large enough to allow accurate measurements. Solid evidence came from the off-road vehicles Opportunity and Spirit. During the dust storms the solar collectors were covered with grains of sand. The way the sand moves is by jumping from place to place. In places where there is no evidence of dune movement, they are cemented together (6). During the 105-day filming in the dune field in Nili Patera, changes in the position of the dunes were observed. It turned out that the ripples moved 2.6 meters during this period, which contributed to the overall movement of the dunes. It also turned out that the movement of the dunes in this place is similar to those found in Valley Victoria in Antarctica. This means that the rate of changes in the surface is similar on both planets (7). The condensation of CO2 towards the winter season in the North Pole covers the dune fields in the area which surround the permanent water ice dome. The CO2 evaporation in the spring causes the erosion of the dunes. The erosion process is reminiscent of erosion that carves the forms of permanent spider channels in the Southern Hemisphere (8).
minerals
Minerals formed by water were found in two places in Noctis Labyrinthus. These clays are smectitites of iron and magnesium and that they are younger than Noctis Labyrinthus compared to those found elsewhere on Mars. This means different watery environments in these depressions compared to what happened elsewhere on Mars. This type of mineral is characterized by the fact that it expands and contracts when water is absorbed into it. These minerals contain iron and aluminum and iron or magnesium in their structure. These minerals are formed by the passage of other ferrous minerals in the presence of non-acidic water. Smectites were found in other places on Mars in connection with an earlier geological period - Noachian age (9).
In Mawrth Vallis, a layer of aluminum clays was found covering a layer of iron or aluminum clays, indicating changes in environmental conditions. Aluminum clays can be formed by washing with water near the surface of the ground and iron and aluminum clays below the ground (10). In the Columbus crater, sulfates were found on clays, which indicates that this crater was once a lake. The sediments of the sulfate salts surround the crater and they were deposited after the formation of the clays during the drying of the lake (11).
Sources
1. Elizabeth Z. - "Mars crater actually be ancient super volcano" 22.10.2013
http://www.marsdaily.com/report/Mars_Crater_Actually_Be_Ancient_Super_ Volcano_999.html
2. "Lava flows carve Mars valleys, study" 26.4.2012
http://www.marsdaily.com/report/Lava_Flows_Carves_Mars_Valleys_Study_999.html
3. "Impact atlas catalogs over 635,000 Martian craters" 12. 6.2012
http://www.marsdaily.com/report/Impact_Atlas_Catalogs_Over_635,000 _Martian _Craters_999.html
4. "Ice clad beauty on silver island of Mars" 8.10.2012
http://www.marsdaily.com/report/Ice_Clad_Beauty_On_Silver_Island_Of_Mars_999.html
5. PIA17750: Mars orbiter laser altimeter, thermal emission imaging system
http://photojournal.jpl.nasa.gov/catalog/PIA17750
6. "MRO catches Mars sand dunes in motion" 21.11.2011
http://www.marsdaily.com/report/MRO_Catches_Mars_Sand_Dunes_In_Motion_999.html
7 Katie N. - "Technology developed at Calthec measures Martian sand movement: 10.5.2012
http://www.marsdaily.com/report/Technology_Ddeveloped_At_Althec_Mmeasures _Martian_ Sand _Movement_999.html
8. "Changes on Mars caused by seasonal thawing of CO2" 25.1.2013.
http://www.marsdaily.com/report/Changes_On_Mars_Caused_By_Seasonal_ Thawing_ Of _CO2_999.html
9. "Young clays on Mars could have been habitable regions" 20.9.2011
http://www.marsdaily.com/report/Young_Clays_On_Mars_Have_Been_Habitable _Regions_999.html
10. PIA15098: Chemical alternation by water, Mawrth Vallis
http://photojournal.jpl.nasa.gov/catalog/PIA15098
11. PIA15099: Sulfates and clays in Columbus Crater, Mars
http://photojournal.jpl.nasa.gov/catalog/PIA15099
After midnight it's hot on Mars - first part of the review on MRO findings
2 תגובות
The home planet has many stabilizers: a good distance from the sun, converging oceans, an appropriate size that creates an ideal gravitational force, a moon that protects + stabilizes, and of course the person that creates a comfortable living environment for him even in the most difficult places. For Israel, there is enough water even in the desert region. So the earth does not go to nowhere.
Just as in the past there was water on Mars and perhaps an atmosphere and today there is none, life on Earth is also seemingly on borrowed time. The technology needs to mature to protect against asteroids, and we have about a billion and a half years until the expansion of the sun, to find an alternative home. On Mars we have not seen any fossil remains of life in water so far, etc. Either a billion years have passed, or we haven't looked deep enough, or there was no life there.