Our Solar system was born 4.6 billion years ago. Below is link to Universe Today news article where chemist Steven Benner explains that after birth of the solar system, the best place for the birth of life was the planet Mars. The best conditions for forming the RNA-molecule were on Mars. The RNA works with the DNA in our every cell. According to theory the life in form of Microbes, including DNA and RNA, would have been transported to Earth with meteorites. When an asteroid hits a planet it can kick off stones, carrying microbes, to space. And later these stones, meteorites, can hit another habitable planet, like Earth. It has been estimated that about 5 billion meteorites, originated from Mars, have been hitting Earth during 4 billion years. After birth of Solar System Mars also cooled earlier than Earth, so the conditions were good for birth of life in Mars much before the Earth. Read more:
Birth of life on Mars:
Universe Today 30.8.2013: Are We Martians? Chemist’s New Claim Sparks Debate
Transport of life to Earth:
European Planetary Science 13.8.2013: Could life have survived a fall to Earth?
Interesting article from Universe Today 29.7.2013 is:
Is Life On Mars Related To Life On Earth?
After the birth of the solar system Mars planet was warm planet with oceans, lakes and rivers maybe for 1 to 3 billion years. Also the atmosphere of Mars was thicker. Mars has liquid water even today. The water is mixed to soil and underground there is probably large reserves of water. On equator the temperature of air on day can reach +20 degrees Celsius and at night -80 degrees. The temperature of surface soil can reach +36 degrees Celsius for several hours during day at equator [63]. On polar caps the temperature is -120 degrees Celsius. The atmosphere pressure of Mars is now 0.8% of Earth atmosphere. Atmosphere is mostly carbon dioxide. The chemistry of Mars and low atmospheric pressure keeps the martian salty water liquid in temperature range -70 degrees Celsius to +10 degrees Celsius [132,133]. That means that at equator of Mars the water mixed in the soil is in liquid state almost all the time.
Gravity on the surface of Mars is 38% of the gravity on Earth surface. There are occasional sandstorms. Year takes 686 days. The tilt of the rotation axis is 25 degrees. So there are yearly seasonal changes in weather conditions. In springtime the water ice of polar cap melts and water vapor clouds bring moisture to middle latitudes. After that large dark greenish areas appear in Mars. Those you can see in Hubble Space Telescope images below. This phenomenon has been known and observed in Mars since 1800 century [ref.63, MARS The Living Planet]. In Hubble images below I have marked with an arrow the Schiaparelli crater near Sinus Meridiani, so that comparison of images becomes easier. You can see that when the ice from south polar cap is small year 2005 the dark greenish areas cover more widely the southern hemisphere. The variations are not caused only by the sandstorms.
If the RNA and life was born in Mars, as Steven Benner proposes, then probably the evolution process would have continued also in planet Mars. On this web-page we study pictures taken by NASA Mars rovers Curiosity, Opportunity, Spirit and Perseverance, to see if there are any signs of past or present life on Mars. Curiosity landed on Mars in August 2012 and Opportunity and Spirit January 2004. We also check the results of science teams which have tested Earth microbes and lichens on simulated conditions of Mars. We handle the results of first ever life detection experiment on Mars, the Viking 1976 mission Labeled Release experiment by Gilbert V. Levin and Patricia Ann Straat . And we get to know the planetary protection issues rised by Carl Sagan , Barry E.DiGregorio and John D. Rummel . The theory by Steven Benner on life born on Mars and carried to Earth by meteorites, is actually a subset of Panspermia theories for which modern versions were developed by Sir Fred Hoyle and Chandra Wickramasinghe .
Sol is the day of Mars, 24 hours 40 minutes. On this page I mention the Sol-x when a Mars rover took the picture. With that information You can fetch the original picture from Curiosity, Perseverance, Opportunity or Spirit rover archives ( Curiosity , Perseverance , Opportunity , Spirit archives), which contain now over one million images. If there are hundreds of images on certain day, I have also mentioned the exact time UTC to make finding easier. I tell also for the images the exact archive identity which for Curiosity looks like 0304MH0265000016R0_DXXX, where 4 first digits is Sol number. From this identity it is possible to create direct link to image in archive like this:
http://mars.jpl.nasa.gov/msl-raw-images/msss/00304/mhli/0304MH0265000016R0_DXXX.jpg (MAHLI)
http://mars.jpl.nasa.gov/msl-raw-images/msss/00186/mcam/0186MR0927120000E1_DXXX.jpg (Mast Camera).
For Opportunity and Spirit both Sol number and identity are needed to form web-link, for example Sol 88 Mast camera image 1P135994587ESF1409P2542L4M1 by Opportunity:
https://mars.jpl.nasa.gov/mer/gallery/all/1/p/088/1P135994587ESF1409P2542L4M1.JPG
Example of Perseverance file names:
Mars_Perseverance_NLG_0002_0667130892_961ECM_N0010052AUT_04096_00_2I3J01
NGL = Navigation Left Green, 0002=Sol 2.
I started the systematic visual study of Mars rover images, one by one, year 2013. Time spent in archives until 2017 is about 2000 hours. As a result of the study in this web page there is about 270 objects presented for which we can ask the question: Is this life or not, either past or present? Some of the objects have been presented earlier in NASA press releases, but most of the objects have not been presented. The study presented here got major improvements when I started co-operation with biologist Dr. Lyall Winston Small .
in October 2015. On year 2017 I was invited to Astrobiology meeting SoCIA 2018 in University of Nevada to present this study. See NASA Event description: Social and Conceptual Issues in Astrobiology (SOCIA 2018) . On 2019 my abstract Visual identification of Extant Martian life was approved on the agenda of NASA organized conference in Carlsbad, New Mexico Mars Extant Life: What’s Next?
Below is Opportunity view from Meridiani Planum, Sol 17, year 2004 and Curiosity view in Gale crater, Sol-538, year 2012.
Below left is a map of Mars with positions of Mars-landers. Blue areas are the ancient ocean floors. Green areas are sea-shore. Red areas are high lands. Curiosity and Opportunity are still working.
On right is view from Phoenix lander in middle of ancient ocean, year 2008. The rocket engines of Phoenix blew off 10 centimeters of sand. Under that a layer of ice was uncovered. Latest studies show that the ice layer may be several hundred meters thick:
H.Kurokawa 2014: Thickness of Martian ground ice: Implication from multi-water-reservoir model.
On equator, the results by Curiosity show that the surface soil contains liquid water even today (source:
Morten Bo Madsen, April 2015: Mars might have liquid water ).