Astrobiologists think it is unlikely that a type of life more complex than simple bacteria would be found on Mars.
Mars has always been considered the planet in the solar system most likely to host extraterrestrial life. Since the second half of the last century, NASA has landed numerous exploration devices on or in orbit around Mars, including Curiosity and Odyssey, and some of them are still operating today.
What these detection devices “see” is a desolate and lifeless land. The surface of Mars is essentially a desert without stable liquid water. The atmosphere, dominated by carbon dioxide, is thin and cold, and dust storms often occur. They dug up soil and analyzed it for traces of microorganisms and organic compounds. Nothing was found. The Earth-like Red Planet appeared to be a frozen desert bathed in ultraviolet raysmortal and apparently devoid of any signs of life.
However, with the deepening of Mars exploration, scientists' views began to change. It might be too hasty to say that Mars is not a home for life. In recent years, more detailed photos of Mars have revealed what appear to be floodplains, dry lake bottoms and even remnants of ancient oceans.
The surface of Mars would be terrifying for any life that relied on liquid water as a source. Although there is some ice at the poles, the temperature is too low to melt. Even if it melts, the liquid will evaporate quickly because Mars' atmosphere is less than 1% of Earth's atmosphere. Mars, which once had liquid water and heat, is estimated to have disappeared about 3.5 billion years ago. Today, the best hope for life there lies underground. Since someMicroorganisms can live deep underground, the energy for their survival does not come from sunlight, but uses the chemical energy and thermal energy of gases and minerals in the earth's crust to convert it directly into biological energy, thus maintaining a food chain independent of surface organisms.