The arrival of the first humans on the Red Planet, besides the journey itself,
poses a major survival challenge. Mars is an extremely inhospitable planet for
life, especially because of the large amount of radiation hitting its surface,
the atmosphere being too fine to absorb harmful radiation. But there is a
simple solution considered for some time, and which seems promising according
to a new study: to exploit the Martian caves, or rather their entrances.
Mars has neither a global magnetic field nor a thick atmosphere like the
Earth ... Its surface is therefore exposed to dangerous ultraviolet (UV) and
ionizing radiation from the Sun, which poses a major problem for future
human explorers. Anything living on the surface of the red planet would be
exposed to doses of radiation 900 times higher on average than those to
which it would be exposed on Earth.
However, images of the planet from orbit have shown what appear to be
entrances to caves, and the insides of these caverns could be protected from
those harmful rays. Daniel Viúdez-Moreiras at Spain’s National Institute for
Aerospace Technology has now calculated how much UV radiation would still
make it into different types of caves at various locations on Mars.
Martian caves: 98% less UV radiation
He found that in many cases UV radiation levels inside caves were around 2%
of surface levels. These radiation levels are low enough to be relatively
safe, but high enough to support organisms that need light to produce energy
through photosynthesis.
However, It isn’t clear whether ionising radiation – which is potentially even
more dangerous than UV – would be blocked out in the same way, but it is
likely, according to Viúdez-Moreiras. “Ionising radiation doesn’t present
exactly the same behaviour as UV radiation,” he says. “However, it is expected
that ionising radiation will also be strongly attenuated in pit craters and
cave skylights.”
The appeal of this finding is twofold: Caves can be safe places for human
explorers to hide from extreme Martian surface conditions (including
sandstorms), and they can also be some of the best places to research. signs
of life on the red planet. No lander or rover has ever visited a Martian cave,
but doing so would be the best way to find out if they are actually habitable,
says Viúdez-Moreiras.
Reference:
The ultraviolet radiation environment and shielding in pit craters and cave
skylights on Mars
by Viúdez-Moreiras DOI:
https://doi.org/10.1016/j.icarus.2021.114658
Tags:
Space & Astrophysics