Name: なぜ私たちは小惑星に「弾丸」を撃ったのか？ (Why Did We Just Shoot A “Bullet” At An Asteroid?)
Uploaded: 2021-01-14T09:58:50.000Z
Duration: 6 min 9 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

The universe is a tantalizing realm of billowing galaxies, terrorizing black holes, mysterious

These lone grey worlds seem to have all the hype right now and, if we have so much going

on in the universe, why are we so focused on sending spacecraft to these drifting rocks?

I mean they’re not exactly easy to explore.

Japan’s Aerospace Exploration Agency learned that the literal “hard way” when their

spacecraft, Hayabusa2, had to launch a “bullet” into the rocky surface of asteroid Ryugu.

(Of course it was for data collecting purposes) but it was never supposed to be that way.

JAXA scientists anticipated the asteroid to have regolith, or a powdery surface of pulverized

material of ice, and dust This would be easy for Hayabusa2 to collect a sample of and add

to the regolith material that was brought back from asteroid Itokawa on the first Hayabusa

But upon arrival, they were met with the opposite; a graveled hard terrain.

With some quick thinking, scientists made adjustments to their collection tactics before

our buddy H2 made its landing–and in doing so, here on earth, they entirely replicated

the surface of an asteroid and shot it with a copy of their sampling instrument.

All their testing proved successful when, on February 22nd, 2019 the spacecraft blasted

the surface of Ryugu, collecting a piece of the asteroid, which is now is on its way back

But that’s not the only sample we’re expecting to arrive to Earth in the coming years.

NASA’s OSIRIS-REx spacecraft is on a mission as well, to investigate another asteroid named

Scientists recently discovered by chance that this is a rare class of asteroid, which ejects

its own mass into space leaving a trail of tinier rocks in its wake.

But Hayabusa2 and Osiris-rex didn’t travel so far to check if asteroids are bullet-proof

I mean they did, but more importantly NASA says that asteroids are time capsules of our

solar system, and these investigative missions are a way to unravel a few mysteries we still

have about how it all formed and how we got here.

Like one of the biggest asteroids may have delivered the elements of life to Earth.

Scientists believe that asteroids like Bennu which are carbon-rich, collided with our planet

And while the rocks didn’t have oceans on them, they could have had water molecules

lurking within its mineral structure, and helped begin the vast life we now know and

There’s also the idea that while earth might have been given life from an asteroid, they

may have also supplied the foundations for the planets themselves.

In the early beginnings of our solar system, there were just tiny particles of dust, made

of rock, metal, and ice swirling around our young sun.

But as time passed some bits fell into the sun and others stuck together; creating asteroids,

but maybe also getting bigger into planetary bodies.

We have evidence that previous asteroids we’ve visited with NASA’s Dawn spacecraft, Vesta

and Ceres, were internally layered with materials, with the core being the densest part.Indicating

both asteroids were growing to be planets but they never gathered enough material to

So an asteroid could be a leftover relic from that early evolution period of our solar system

But now that I’ve explained some ways asteroids are awesome, there’s always a little disclaimer

and this one is that asteroids can be hazardous to earth.

We actually have a program called the Planetary Defense Coordination Office and they use a

collection of instruments in the Near-Earth Object (NEO) Observations Program to keep

tabs on any and all asteroids that flyby, or enter our atmosphere.NASA is even working

on a redirect mission called DART where Bruce Willis takes a team of oil riggers – jk,

There’s no Bruce, but this is a real mission.

And emerging research like this simulation from John Hopkins University shows that it’s

much more difficult to destroy an asteroid than we previously thought.

So this all may be new to you, but we’ve actually been hunting asteroids for a while

Back in the early 2000’s, NASA’s NEAR Shoemaker was the first spacecraft to orbit

Now missions like this are standard when going to small bodies with OSIRIS REx, Hayabusa1

Hayabusa2, although not back yet with its sample, has already detected that the Ryugu

asteroid is drier than anticipated and that it’s quite young, only around 100 million

This suggests that wherever it stemmed from was probably devoid of water, too.

Which might change our current understanding of what the universe looked like 100 million

And OSIRIS RE-x, remember lucked out with Bennu being an “active asteroid.”

Out of the 8,000 asteroids discovered, there have been just 12 observed releasing their

So all observations from Bennu are valuable and it has plenty of time to prepare for its

NASA wants to send a spacecraft, for the first time, to a nearly entirely metal asteroid

Psyche is special because it might be a piece of a metallic core that’s similar to Earth’s

Earth’s core is way too hot to investigate and now it’s our opportunity to do so and

understand how Earth and other rocky planets formed.

Plus, the center of our magnetic field is our metallic core, sooo this might help us

(hopefully) NASA’s estimated arrival to Psyche will be in 2026.

So floating space rocks such as asteroids, are unique to our understanding of our universe.

They may hold the key answers to our burning questions and all we have to do is capture

Still wanna know more about the missions ahead?

Comment down below on the specifics you’re looking for and check out this video about

Oumuamua, the mysterious interstellar asteroid that flew right by us.

Subscribe for more science in your day and thanks for watching seeker.