Radiation on Mars is a significant problem both solar radiation and cosmic rays are both
a problem.
We don’t have a dense atmosphere on Mars.
It’s only about 1/100 the density of the atmosphere on Earth.
And therefore there are not a lot of particles in the air for solar rays coming from the
sun to collide with and be deflected as there are on Earth.
Mars also doesn’t have a Van Allen belt like we have which deflects a lot of solar
radiation.
And it does not have a molten core like we have which creates a magnetosphere around
the Earth which also deflects a great deal of radiation.
So Mars is a very radiated place in many ways.
And people will need very, very thick walls on their buildings if they build above the
surface to stop solar radiation and to hinder most of the cosmic rays.
Cosmic rays are of mysterious origin.
We don’t actually know where they come from but they are little bits of atoms that are
traveling at high speed.
And these particles can penetrate ten feet of steel.
We are exposed to them on Earth.
Pilots who fly transcontinental airline routes are actually exposed to quite a bit of cosmic
radiation.
Cosmic radiation, all radiation undoubtedly in the long run causes cancer in human beings.
One of the tradeoffs you might say of going to Mars is that you are going to get more
radiation than you get on Earth.
Both on the trip out there and when you get to Mars.
One of the defenses we will have against radiation on Mars is a spacesuit.
But on Mars we’re not going to wear spacesuits that look like these things in the movie Gravity
that are kind of like deep sea diving bags and this huge bubble on top of your head and
they’re incredibly awkward and difficult to move around in and you’re kind of encapsulated.
A woman at MIT who has actually been nominated to be the number two person at NASA, a woman
named Dava Newman has developed a spacesuit that looks more like something you would wear
as an exercise clothing in a gym.
It’s very tightfitting kind of spandexy like.
It has metallic threads in it and it’s fabulous at protecting you from radiation at least
in a short period of time.
It also does another interesting thing which is because the atmosphere on Mars is so thin
you would not explode and you would not have nitrogen narcosis like you do with the bends.
But you can’t survive long on Mars because just walking outside if we forget about the
radiation problem because there’s not enough pressure on your skin.
On Earth we have 15 pounds, 14.7 pounds of atmosphere piled up above us that presses
on our skin at all times.
And as human beings over a long period of time we have evolved in our bodies to be pushing
back.
So underneath our skin essentially our bodies are pushing out at all times to compensate
for that 15 pounds of atmospheric pressure.
Now you don’t need 15 pounds of atmospheric pressure pushing on you to kind of keep you
from turning into a balloon.
But you do need about 5 or 6 pounds.
And a sort of spandexy kind of spacesuit will create enough pressure against your skin so
that that problem is solved.
So we have to do everything we can to protect people from radiation on Mars.
And that probably means initially living underground.
Eventually we will live above ground.
It’s not that dissimilar from Antarctica.
You can’t to outdoors in Antarctica in the winter.
But people survive just fine in Antarctica.
There’s – but radiation is a big bugaboo.