There Is Life On Mars
Mars had lots of water, possibly large oceans, long before Earth had even finished forming as the planet we know. 3.8 billion years ago, Earth's oceans formed, and Mars' magnetic field disappeared, which thinned out the atmosphere and let the solar winds evaporate the surface water. According to mineral evidence the water finally disappeared from the Martian surface 2 to 2.5 billion years ago, which has driven life underground if it wasn't already there. By biological means, oxygen started collecting in Earth's atmosphere 2.7 billion years ago and became a dominant component 2.4 to 2.1 billion years ago. This drove anaerobic life underground or places where there wasn't free oxygen.
A life form on Earth could foretell what life beneath the surface of Mars looks like. Microbes named Candidatus Desulforudis audaxviator, feed off chemical reactions triggered by radioactivity, have been at an evolutionary standstill for millions of years. This showed great perseverance and stability for a life form cut off from the surface for millions of years. No one knows if it started its existence under the surface or retreated from the surface.
Mars could have the same kinds of life under its surface where it retreated to when the surface dried up, or was always in existence there. The Candidatus Desulforudis audaxviator was found in deep underground caves. There could be a lot of different kinds of life forms powered by radioactivity under the Martian surface living in caves and far reaching cooled off volcanic tunnels.
Science asks if life could exist deep underground on Mars? I say yes, it is more than entirely possible that microbial life started up on Mars when water was present just like life started up very early in Earth's history. The time it took to go from a water covered planet to a dry surface one could have given the existing life time to go far below the surface where it still is today.
The Martian surface temperature has been measured to be from 37 degrees F to -131 degrees F. This could indicate that it could be fairly warm far below the surface where underground liquid water deposits and greenhouse gasses could support microbial life.
Mars' original atmosphere may have been similar to Earth's atmosphere before the oxygen showed up. The surface of Mars might be a snapshot of what the earth's surface looked like chemically 3.8 billion years ago. Earth's surface has been continually changing due to the movement of the tectonic plates. One possibility is that Mars was originally covered by a molten surface that cooled off, magnetized by the magnetic field. The crust cooled down but left a molten layer below it which insulated the molten core from the cooling crust. This molten rock core has kept the iron core liquid.
The surface of Mars is 3.8 billion years old — this is extremely old. We cannot dream of rock preserved at that age on Earth in that preservation state,” Rapin said. “It’s pristine compared to almost nothing left undisturbed on Earth's surface from that long ago.”
The Martian atmosphere, though 100 times thinner than Earth's atmosphere, is incredibly active. With huge dust storms of heavy particles and snow storms that precipitate frozen carbon dioxide, the density of the atmosphere can easily change 8 to 10 percent in a short amount of time. Studying how the Martian atmosphere moves particles around might help us understand how Earth's atmosphere moves particles around, a very difficult process to understand due to its high density and large mixture of components.
3.8 billion years ago, the Martian atmosphere would have been a lot wetter and warmer than it is today. The atmosphere probably contained carbon dioxide, nitrogen gas, hydrogen, argon, water vapor, and outgassing from volcanoes. This would be similar to Earth before oxygen became the dominant force in Earth's atmosphere. An atmosphere that supported the development of life on Earth.
Mars core is still molten. There is no explanation for how the magnetic field started, nor how it ended. It could have happened suddenly or slowly. The core's components have been determined by computer modeling. It predicts the core has some lighter weight elements in it, like Earth does. The core is also surrounded by a molten layer around 100 miles thick of molten rock and radioactive materials that keep the core liquid. Earth does not have a molten blanket of rock surrounding the core. Mars apparently does not have a solid core inside the liquid core like earth does.
Good seismic readings were only obtained when a meteor hit Mars hard enough to create a good acoustic wave to travel through the core region and come out exactly where a seismic listening device, the Insight Lander, could detect it. The Insight Lander only operated for 4 years, twice as long as expected. It ran out of power because the panels got covered with dust. The mobile units can take limited readings but aren't as accurate as the Insight Lander was.
Mars core has molten iron in it but it’s not creating a magnetic field. The crust is heavily magnetized. The magnetic field might only have lasted a couple of hundred million years. The reason put forward for the magnetic field ending is the same reasoning put forward 23 years ago in 2001, basically no one knows. One theory is that a large moon orbiting Mars, now gone, created a convection flow in the core which created the magnetic field. One intriguing thought is that if the iron core starts to solidify it might start up the magnetic field again.