After careful selection, the global migration of Mars, 'Mars One' program, has selected 100 people as a shortlist from 500 volunteers. What makes the one-way trip so attractive, with no prospects of a return to Earth? Let's talk about Mars itself. 

There is water on Mars. Due to low temperatures, water on Mars is in the form of ice beneath the surface. If the ice were to melt, there is enough water to cover the entire surface of Mars to a depth of 11 meters. Life cannot survive without water, and Mars therefore possesses this basic prerequisite in abundance.

Scientists speculate that billions of years ago, Mars was most probably like Earth, with a very thick atmosphere, water, ocean and even life. However, low gravity resulted in the loss of atmospheric molecules and therefore Mars become cold and dry and then life disappeared or hid underground.

In addition, a small amount of methane in the atmosphere of Mars has been confirmed, but its origin remains a mystery; it may come from a chemical reaction, or from bacteria - and if the latter, it means that life exists on Mars.

Technically, the biggest problem faced by the program is not technical, but the physical and psychological problems. Currently, flying to Mars from Earth takes about eight months. Such a long journey will bring a lot of problems to the migrants, such as muscle atrophy or osteoporosis caused by weight loss. In addition, more cosmic rays radiation may cause cancer, while psychological diseases may result from living in a confined space for a long time.

Furthermore, even if we successfully reach Mars, building a permanent base is also a challenge. Since the number of immigrants will be limited, most of the labor will rely on robots. Besides farming, food and finding water, the most urgent issue is how to produce oxygen.

So, should we migrate to Mars?

Earth's population is growing, and one possible solution is to allow some people to emigrate to other planets. If Earth were to collide with an asteroid, humanity will be destroyed, as happened with the extinction of the dinosaurs 70 million years ago.

This article was edited and translated from 《为什么想要移民火星（科技大观）》, source: People's Daily