How Gaia Changed Astronomy Forever | Space Time

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The great advances in any science tend to come in sudden leaps. April 25th of 2018 marks the beginning of just such a leap for much of astronomy. In the early hours of the morning, the Gaia mission’s second data release dropped. Our understanding of our own galaxy will never be the same again.

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Previous Episode:
The Star at the End of Time

The Gaia satellite was launched in late 2013, entirely built and operated by the European Space Agency. It’s primary goal is to map the stars of the Milky Way with a scale and precision orders of magnitude greater than ever before. Gaia’s predecessor, Hipparcos, catalogued 120 thousand stars, Gaia blows it out of the water with positions, colors and brightnesses of nearly 1.7 billion stars. Gaia can see orders of magnitude fainter and further away than previous missions. But its greatest superpower is its precise astrometry – Gaia can pin down a star’s position to the equivalent of a human hair’s width at 1000 km. That’s one-to-two thousand times smaller than the resolution of the Hubble Space Telescope.

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QUANTUMquest The billionaire salesman cowboy says:

I wonder why he is standing on his tip toes??

Hurr Durr says:

you can't calculate the relativistic motion of a billion stars, all influencing each other, can you?

rohit meena says:

thank you gaia for protecting us.

MaSai Mai says:

Astonishing! Thanks!

V. Gedace says:

lol, sorry but this guy looks strange … was his head made bigger (via photoshop or so)? What shoes does he wear? High heels? And he uses "Merkels Raute" lol … strange…

Dustin Jones says:

Mapping 1.2 billion stars with pin point accuracy, check. Ending extreme poverty on planet Earth, …still working on it.

Dmitry Lapshukov says:

We are Gaia

beforeoriondotcom says:

An alternative view –

AstCeriskos says:

If every dot of light is a star, what’s in the dark inky parts in the middle?

kobla nyomi says:

00:00 The Great Advances In Any (Gaia) Science. Coincidence?

will2see says:

Possible? Sure. Worth an episode? Hell, yeah. 🙂

Regicidal Satanist says:

Can we just be fucking space pirates yet? Thanks!

Sambhranta Gupta says:

Wow!! That's so much new discovery!

Sid Gillespie says:

What is the music that starts playing toward the end of the video?

Sylak says:

So basically, we now have a Astrogation map? Prep the Hyper drive people!

Rob Harwood says:

Dude, I love your humour. Joke at the end much appreciated! XD
Great episode, as always. I thought it was going to be about the Gaia Hypothesis. Hadn't heard of the Gaia mission before; it's amazing. Is it ongoing? Will it give us more information over time?
PS: Hopefully PBS Space Time will outlive the last red dwarf. (^_^)

Rob Harwood says:

Matt, please let us know if Space Time is in danger of being cancelled like Infinite Series. It's frightening that PBS Studios would just cancel them with no explanation.

Pranjal Dubey says:

Please make a video on magnetar

beejum ittahb says:

after spending trillions on space exploration we should indeed be so v grateful that we are beginning to know so much more _because once we ve fu cked the earth with advances in all our technology we can continue to fu ck our new host planets that we will urgently need to support life

Madhijz -spacewhale says:

Name dropping Isaac Arthur? Yusss!

Joseph Salomone says:

It does all that and tracks my hiking routes? It is like the end all be all satellite.

brian says:

What time is it?

Bil Cozbi says:

Id really love to watch these videos. But the narrators elocution makes it unwatchable. I don't know why you can't replace him. Maybe native English speakers have no problem with making out what he says, but what about the rest of us? Not like I usually have tough time listening to English speakers. I feel the content of the vids is too valuable to not warrant a better delivery. Thx

Jonathan Bertman says:

Did Gaia show any evidence of non-celestial mechanics (e.g., possible evidence of extraterrestrial technology)?

Thought Stricken says:

Is it just me, or does the Gaia H-R diagram resemble a whale and it’s calf? So long and thanks for all the fish indeed.

Mil Santos says:

Viva Gaia! Thanks for the great video!

Thetreetroll says:

We should make a mission to recover the Hubble and bring it back home. We need practice in orbital recovery.

Steve Phillips says:

This is how rats gauge distance too, wobbling their heads to see what moves and by how much. Rats in space!

Tx240 says:

If Gaia can "see" to the center of our galaxy and a satellite taking images for Google maps can show detailed earth images, why have we never seen clear images, from space, of the supposed lunar landing mission sutes?

The satellite that took pictures of Pluto had clearer images than the Japanese satellite that recently orbited the moon.

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