What does it mean that there is no magnetic field on Mars?

There is no communication signal with atmosphere and some sense of direction. Scientists predict that the problem of Mars without magnetic field will be solved sooner or later (I don't think it's easy) in the case of Mars colonial plan. Many people think that the problem of magnetic field on Mars must be solved, because it can stabilize the atmosphere of Mars. They even think that it is meaningless to try to restore the atmosphere on Mars unless the magnetic field problem can be solved.

However, this is not the case. There is no doubt that because there is no magnetic field, the atmosphere of Mars was brought into outer space by the solar wind. However, if we can create the same atmosphere on Mars as the earth, it will take about one million years for the solar wind to take away one percent of the atmosphere. So this is not a problem, but the impact of solar radiation on the health of colonists.

In fact, the solar radiation on Mars is not as serious as people generally think, that is to say, in a short time, people wearing spacesuits will not necessarily die once they enter space. However, when people establish permanent settlements on Mars, with the passage of time, residents on Mars will gradually suffer from various diseases caused by increased radiation, mainly the increase in the number of cancers and diseases that cause various genetic abnormalities in newborns.

However, this is not the case. There is no doubt that because there is no magnetic field, the atmosphere of Mars was brought into outer space by the solar wind. However, if we can create the same atmosphere on Mars as the earth, it will take about one million years for the solar wind to take away one percent of the atmosphere. So this is not a problem, but the impact of solar radiation on the health of colonists.

In fact, the solar radiation on Mars is not as serious as people generally think, that is to say, in a short time, people wearing spacesuits will not necessarily die once they enter space. However, when people establish permanent settlements on Mars, with the passage of time, residents on Mars will gradually suffer from various diseases caused by increased radiation, mainly the increase in the number of cancers and diseases that cause various genetic abnormalities in newborns.