Origami is the ancient art of Japanese paper folding. For years it has been used to create
stunning works of art. But it has also been used in maybe more surprising ways, like car
airbags, stents and even space exploration.
What we want in space are large structures, not necessarily massive, but large. Which
means you can make them out of thin materials, and whenever you can make them out of thin
materials you can use origami to fit them in these rockets.
Many space projects have used the folding principles of Origami; the solar array wings
on the ISS uses a z folding pattern and the Mars Phoenix lander used a fan-folded solar
array, called the UltraFlex.
Because the biggest rockets we have right now are only about 5 meters in diameter, we
have to come up with a way of folding up this very large structure so that we can launch
it in a rocket, and once it get to space it can unfold itself... origami is one the underlying
mathematics of how large thin sheets fold up.
One origami project currently in development at NASA's Jet Propulsion Lab is The Starshade,
which is essentially a big star blocker. Have you ever tried to take a picture of someone
when the bright sun is beating down on them? Your subject is washed out and you won't
be able to capture any detail. This is the same problem astronomers have when trying
to image exoplanets. Currently astronomers detect exoplanets indirectly using a shadow
technique called the transit method. For an earth sized exoplanet orbiting a sun like
star, they can't be imaged in detail, because the stars they circle are much brighter than
they are. This is where the Starshade comes in, to help block that bright light to better
help astronomers learn more about these mysterious planets and look for biosignatures for life.
One of the ways in which we're thinking about suppressing the starlight is using something
called Starshade, which is a very large external occulter …that blocks out that starlight,
so we can see those really faint planets right next to it. Sounds easy enough, but the Starshade
is roughly the size of a baseball diamond. Because the Starshade is so huge...we have
to come up with a way of folding up this very large structure into spaces that we can launch
it inside a rocket. And once it gets to space, it can unfold itself. Which is where origami
comes in. This is one of the candidate fold patterns that we had for the inner part of
the Starshade, what we call the optical shield. You can mathematically define how this sheet
of paper is folded up, and then by creating what's called an isometric map… you can
define what the creases have to be on a flat piece of paper to allow this sheet to fold
up in this very particular way. And the way it unfolds is just like that. And it's quite
remarkable in its simplicity. This giant space flower may seem simple in design but not in
implementation. The Starshade will need to unfold with millimeter accuracy. Once opened
thrusters will move the craft through space, positioning The Starshade between the star
and the space telescope. With the star now being shaded, the telescope can image the
planet in detail to find out whether conditions for life exist. Origami has been practiced
on Earth for years, and scientists will continue to draw inspiration from it to help
package big space structures more efficiently. From solar sails that use sunlight for propulsion,
to sun-shades for space telescopes like Gaia, and the James Webb once it launches in 2019.
We can take these ideas from origami and apply them to spacecraft structures. Because when
it comes to the future of space exploration, if we want to think big we also have to think
small. For more science documentaries, check out this one right here. Don't forget to subscribe
and keep coming back to Seeker for more videos.
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