Name: 摺紙如何改變火箭設計 (How Origami Could Change Rocket Designs)
Uploaded: 2021-01-14T10:38:08.000Z
Duration: 5 min 11 s
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We've had the technology to reuse rockets for decades now;

But the Shuttle's solid rocket boosters weren't too impressive in their return home.

Now we're in the era of rockets that can land themselves on floating platforms.

and those tiny legs at the bottom have to withstand a lot of force in the process.

So one team of engineers is trying to develop a new material

that could lessen that force, and in turn, soften that dangerous landing.

Last week in the journal Science Advances,

they showed how they were inspired by the ancient art of paper folding: origami.

Researchers based at the University of Washington decided to try

counteracting the compression waves, basically a pushing force,

that would travel through a material during a collision.

Like when the legs of a rocket hit the landing pad.

For that, they designed a type of mechanical metamaterial.

Metamaterials are a type of artificial material built from repeating units,

think Lego bricks, that engineers can manipulate to create new properties.

It's figuring out what those bricks need to look like that's the tricky part.

This team used a laser cutter to form a specific pattern of creases in a piece of paper,

then folded that into a cylinder-esque shape.

On either end they glued an acrylic hexagonal cap.

So when the cap was pushed on, the cylinder buckled in a pattern determined by the creases.

But it could also spring back into its original shape.

They linked 20 of these cylinders together in a column.

Then they subjected their column to compressive forces.

And their column was able to transform that push into a pull.

each little cylinder also resisted that push and straightened out slightly.

This created a pull within the structure, or what's technically known as a rarefaction.

And as both the push and pull propagated along the column,

the pull actually traveled faster, so the whole structure resisted being squished.

What's also cool about this research, besides the whole origami rocket part,

is that previous strain-lessening methods required hundreds of metamaterial units.

This new origami structure needed only ten.

There are some limits to the research, though.

The team only looked at the system in one dimension.

Also, they had to do the paper folding themselves,

so, any real-world application of this tech is going to need to develop beyond that.

But this new method doesn't need to be limited to rockets,

it could be applied to all sorts of situations where collisions are involved,

It's a new way to protect against all sorts of dangers.

And another, more astronomical danger was in the news this week.

are a stream of high-energy particles thrown off the Sun with little warning.

They're the most powerful magnetic anomaly our star creates,

and when the particles reach us they can interfere with electrical equipment,

including satellites and, if the CME is powerful enough,

things like radio transmission down here on Earth.

But our Sun isn't the only star that creates these blasts.

And this week in the journal Nature Astronomy, astronomers have turned their attention

to coronal mass ejections coming from something other than our sun.

A team based out of Palermo, Italy used the Chandra observatory to study

the x-ray light emitted from the star dubbed HR 9024,

which is located about 450 light years away.

It's also a bit bigger than our Sun, as well as a bit hotter, so bluer.

But most importantly, it's considered “active”,

meaning it emits way more energy per second on average.

And they spotted a flare, analogous to a solar flare, coming from this star.

By analyzing the star's spectrum, or its light signature,

they were able to identify specific elements present in the flare.

Different elements show peaks in the spectrum at different wavelengths.

In order to separate what's coming from the star's atmosphere and the actual CMEs,

This is the same effect that makes an ambulance siren coming toward you sound higher pitched,

and one moving away from you sound lower.

Light or sound waves moving toward us are compressed relative to us,

For sound, that changes the pitch; for light, the color.

So a light source moving toward us gets bluer, and moving away, gets redder.

By tracking specific peaks in HR 9024's spectra, comparing where they should be

if they're not being ejected to where they appear, the astronomers could tell

which elements were moving toward or away from us.

And that's the material that's in the flare.

They found sulfur, silicon, and magnesium inside a giant plasma loop,

On top of that, there was an additional line of oxygen that was cooler and out of step with the flare.

That, the researchers think, indicates the presence of a CME.

Based on that assumption, they estimated that CME's mass: about one billion billion kilograms.

But they weren't able to determine if any of that mass successfully

escaped the star's gravitational pull and would go forth to irradiate hypothetical planets.

In comparison with CMEs from our Sun, it released more energy,

but not nearly as much as they had predicted.

This is just one initial step in actually investigating how stars different from our Sun behave.

Math only gets us so far, and this result might mean

stellar CMEs are more different than we thought they'd be.

Which could mean a lot of things, and even, theoretically,

influence the development of life on those stars' planets.

Thanks for watching this episode of SciShow Space News,

and thanks to our great Patreon supporters who help us make episodes like this.

If you want to join them, check out patreon.com/scishow.

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摺紙如何改變火箭設計 (How Origami Could Change Rocket Designs)

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