Why did human immigrants practice on Mars first?

Mars is the planet closest to the earth and most similar to the earth's environment, so it has become the first stop for space immigrants.

Mars is the most earth-like planet. The rover confirmed that there used to be a lot of liquid water on Mars, and now there may be a lot of ice underground. In some areas with relatively high temperature, there may be underground lakes, so there may be some lower organisms.

Mars orbits close to the earth. The ground is composed of rock and sand, and there is atmosphere on the surface. The main component of the atmosphere is carbon dioxide, and there is water at the poles. Although human beings can't live directly on the surface of Mars, it is most likely to be suitable for human survival after certain transformation.

Mars explores life

In 2000, a Martian meteorite, numbered ALH8400 1, was discovered in Antarctica, USA. The National Aeronautics and Space Administration (NASA) claims to have found some micro-fossil-like structures on this meteorite. Some people think that this may be evidence of the existence of life, but others think that this is only a naturally occurring mineral crystal.

But until 2004, neither side of the debate gained the upper hand. The Viking probe has done experiments to detect microorganisms that may exist in Martian soil. The experiment was limited to the landing site of the Pirate and gave a positive result, but it was later denied by many scientists.

Existing biological activities are also one of the explanations for the existence of trace methane in the Martian atmosphere, but people usually agree with other explanations that have nothing to do with life. In the future, if humans colonize aliens, Mars is likely to be the preferred destination because of its friendly conditions (compared with other planets, Mars is most like the Earth). Algae can survive in space, or help people cultivate on Mars. The algae that survived the experiment on the International Space Station were yeast from Svalbard, Norway, and Nostoc commune from Antarctica.