- So Gretchen, what else lives in caves?
- Perhaps the organisms that are most home in caves
are microbes, which are microscopic organisms
that are part of our everyday lives.
The microbes that live in caves could help us
develop new medicines, such as antibiotics.
Scientists are also really interested
in microbes that live in caves called extremophiles
because they have adapted to extreme environments
similar to what we might find on other planets.
Dr. Boston from NASA is going
to tell us more about microbes.
(water drops)
- My name is Penny Boston and I'm
an astrobiologist and a cave scientist
who focuses on geomicrobiology.
I work in the United States, in the state of
New Mexico, and I visit caves all over the world
and look at the microorganisms that live there.
I study what they do to the rocks
and minerals, and unique biosignatures
that they may be producing because of
those interactions with the minerals.
So that's the setting that brings me to caves.
And part of the reason that we are tremendously
interested in the kinds of life forms that we
find in the subsurface is for
a number of different reasons.
One is because they're very poorly studied here on Earth.
There's very little work that has been done on
these organisms, so it's an entire area
of Earth biology that has only
been studied a very little bit.
So that's one major aspect of it.
The second aspect of it, is looking for
environments that have different aspects of them
that might be important models for life on other planets.
So for example, on Earth, we have hot caves,
we have cold caves, we have acid caves,
we have caves with poisonous gases in them.
All of these different kinds of examples
can inform us about how microbial life
rises to the occasion and learns to adapt
and live in these kind of environments.
One of the other important aspects of caves and
space exploration, is that we now know that there
are many caves on other bodies in the solar system,
particularly Mars and Earth's moon.
We have detected and mapped many of these features.
And so, the potential exists for future human use
for human exploration, in these kinds of structures.
The ability of the rock that is the
overlying material over a cave, is very good at helping
to screen out very high energy ionizing radiation.
And this is a major hazard in space flight
and space habitation on other planets.
And so, these natural features, because they
already exist in these environments, provide us
with an ability to actually modify those for
human use, with much less payload penalty
than if we had to take all of that structure
and all of that radiation protection with us.
A very important aspect of being in the
subsurface and using caves as an analog for
extreme environments like other planetary
surfaces, is because it really is
psychologically a transforming experience.
When you go into the subsurface for a short trip
into a show cave, for example, you don't
really feel the full extent of it.
But when you explore caves, and you are in for many days,
your whole sensory abilities are different.
You don't hear the same things that you hear on the surface.
You don't smell the same smells.
You don't feel the wind on your skin in the same way.
And so, you don't see the same way, because you're
restricted to the light that you have with you.
And so, this really is like entering an alien world.
It's like going on an expedition to another planet.
And so, for training people to experience that
as a preparation for operations in extreme
environments and outer space environments,
it's an invaluable analog, and we have used
that in many different contexts.
And so, I recommend it as an experience
that all people who are aspiring to
go into space or do other very
difficult tasks would benefit from.
(drum roll)
- I want to visit caves on other planets.
- That would be amazing, but for now, there's a lot
for us still to learn and discover in caves
right here on Earth.