Why did mankind choose Mars as the research object when exploring the universe and opening up a space residence?

It is reported that the main reasons for human exploration of Mars are:

Mars is the planet closest to the earth, most similar to the earth, and the easiest to detect and study, so it is of great significance to detect it. By studying the evolution process of Mars atmosphere, it is helpful to correctly understand and grasp the changing trend of the earth's environment, and it is of practical and far-reaching significance for human beings to protect the earth's environment and thus survive forever in the universe. Mars exploration plans implemented by various countries all include the task of finding out whether there is life on Mars. The existing detection results show that there are indeed traces of water on Mars. This is of great significance for detecting the origin and evolution of life and manned landing on Mars. In addition, the population on the earth is increasing, but the resources are decreasing, and some of them are almost exhausted. Mars exploration is conducive to expanding human living space.

According to Tollsten Zuo En, director of NASA's Curiosity Project, the landing of Curiosity will help people expand their ability to land on another planet after landing on the moon and shoulder the task of being a stepping stone for human beings to stand on Mars.

According to the new policy, NASA will transport American astronauts to celestial bodies outside low earth orbit, such as asteroids after 2025; By the mid-1930s, American astronauts will be transported to Mars orbit.