Question

What evidence suggests that the biochemistry of life elsewhere would resemble that on Earth?

Answer 1

Evidence of past liquid water on the surface of Mars suggests that this world once had habitable conditions and leads to the question of life. If there was life on Mars, it would be interesting to determine if it represented a separate origin from life on Earth.

The motivation for the search for life on Mars comes from the evidence of past water activity. An image of Nanedi Vallis, which is perhaps the best example of the long-term flow of liquid water on Mars . Other fluids suggested as possible geological agents on Mars include wind, glacial ice, lava, and liquefied CO2. Liquid water, flowing repeatedly and stably on the surface.

To determine if life on Mars represents a second type of life requires that we study biological material: Fossils are not enough. Mineralized fossils or tracks of life would be proof of life on Mars, but would not inform us about the relationship of that life to Earth’s life.

here are several possible places on Mars where we might find evidence of life that can be used to determine if it emerged as a second genesis. Possible targets include: (1) Life in the surface soil, (2) Life in subsurface liquid water, (3) Organisms, probably dead, but preserved in ancient salt or mineral deposits, and (4) Organisms, dead or alive, preserved in ancient ice