Spanish scientists have proposed a method by which you can protect yourself from harmful radiation bombarding the surface of Mars. It is suggested that areas near the entrances to naturally occurring Martian caves would be suitable for this. An article about this was published in the Icarus magazine.
Since Mars, unlike Earth, does not have a powerful magnetic field or a dense atmosphere, its surface is constantly exposed to ultraviolet radiation that is dangerous for all living things, as well as bombardment with charged particles. Any living creature that finds itself on the Martian surface receives radiation doses that are 900 times higher than what it may encounter on Earth.
At the same time, photographs of the Martian surface taken by orbiters often show something similar to the entrances to caves, and the insides of such caves can be protected from harmful radiation. Daniel Viudez-Moreiras of Spain's National Institute of Aerospace Technology analyzed how much ultraviolet radiation gets into different types of caves at different locations on Mars. He found that in many cases, the level of ultraviolet radiation inside the caves is only 2% of the surface. It is not known exactly how ionizing radiation, which is potentially even more dangerous than ultraviolet radiation, will be blocked, but its level should also decrease under the canopies of the caves. “Ionizing radiation does not behave exactly like UV radiation,” says Vioudes-Moreiras. "However, it is also expected to weaken strongly in the depressions and under the arches of the caves."
This leads to two conclusions at once: the caves can serve as a safe haven for future astronauts exploring Mars, and, in addition, they may be one of the best places to look for signs of life on this planet. According to Vioudes-Moreiras, no lander or rover has ever visited a Martian cavern, and it would be worth correcting this omission in the future.