Name: 5個獲得新生命的航天器 (5 Spacecraft That Got a New Lease on Life)
Uploaded: 2021-01-14T10:27:45.000Z
Duration: 5 min 59 s
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Space missions don't always go quite as planned.

And by the time something goes wrong, your spacecraft is a hundred million kilometers

Consequently, space science can get...improvisational.

If a tool is no longer capable of carrying out its original purpose,

Your adjustable wrench's threads bound up?

Well, then you've got a very oddly-shaped hammer!

The folks at NASA have had to apply this school of thought to far more sophisticated equipment,

and sometimes it works out really well for them.

The Hubble Space Telescope has been serviced by astronauts five times since 1990.

Because it's in low Earth orbit, we've actually been able to go there and fix it.

The Kepler space telescope was meant to find exoplanets by continuously watching faraway

a slight dimming of a star's brightness for a specific amount of time, indicating

Through this method, Kepler aimed to identify as many Earth-sized exoplanets as possible,

while looking at a patch of about 150,000 stars.

It had four gyroscopic stabilizers — one stabilizer for each three-dimensional axis,

These were to protect the probe from being pushed around too much by pressure from the

In 2013, four years into the mission, two of the stabilizers had failed.

Which made it too hard to keep the telescope steady —

so NASA put it in sleep mode and went back to the drawing board.

After a few months of hard work, scientists realized they could use the solar wind instead

basically bracing the spacecraft against it and using the other two gyros to keep it in

It would mean they'd need to re-align the telescope every 80 days as it orbited the

sun and slowly shifted its angle relative to the solar wind.

Which meant pointing it at a new field of stars every few months, instead of studying

But these limited “campaigns” returned fantastic results — and buckets of exoplanets

And this isn't the only telescope NASA has had to save.

Spitzer is an infrared space telescope designed to operate slightly above absolute zero to

see distant objects that optical telescopes can't,

such as low temperature and dim objects far away.

Spitzer initially had a life expectancy of two and a half years, which it easily outstripped.

But in 2009, after five and a half years of operating, its liquid helium coolant finally

Spitzer could no longer look at some of the very cool and dim objects it had been designed

But at its new temperature, the telescope could still look at asteroids and comets in

our own solar system, as well as far-off, ancient galaxies.

This was the start of its so-called “warm mission” —

which, at minus 241 degrees, was still pretty chilly.

Spitzer has subsequently observed countless amazing objects in our own solar system, and

But space missions obviously aren't all about looking at things from afar.

Sometimes we want to get up close and personal.

To that end, the Deep Impact mission was designed to slam a probe into a comet while the probe's

In 2005, the 370-kilogram impactor probe successfully smashed into Comet Tempel 1 at 37,000 kilometers

and in so doing, revealed a lot about the nature of comets.

That, and dinosaurs in their graves maybe felt a twinge of catharsis.

The mission was complete, but while the probe had very much crash-landed, there was still

a perfectly functional mothership out there.

So mission managers sent it to do more cool comet science elsewhere.

During its new mission, dubbed EPOXI, the probe flew by another comet, made observations

of Earth and Mars, and even searched for exoplanets.

Eventually though, NASA lost contact in August of 2013.

Then there's the part where NASA used a totally different probe to get more mileage

The Stardust spacecraft, which flew through the tail of comet Wild 2 in 2004,

was similarly successful enough to be given new tasks.

Stardust's visit in 2011 gave NASA the opportunity to observe their handiwork, and to make further

And while we've covered it before, no discussion of spacecraft doing more than their planned

workload would be complete without a mention of the Mars rover Opportunity.

Oppy lasted sixty times longer than its planned lifetime of 90 days,

spending nearly 15 years searching for signs of water and collecting other data on the

but its success speaks to the careful planning and engineering that goes into every device

Space travel is difficult and expensive, so the scientists responsible really care about

Whether it's coming up with clever fixes from afar,

or just making the most of their funding, scientists have gotten pretty adept at getting

everything they can out of their outer space investments.

Thanks for watching this episode of SciShow Space.

This episode, along with every other episode we make, was supported by our patrons on Patreon.

If you're interested in helping us do what we do, check out patreon.com/scishow.