How Gaia Changed Astronomy Forever

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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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.

Hosted by Matt O'Dowd
Written by Drew Rosen and Matt O'Dowd
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[flymypg]

There have always been trade-offs between data quality and quantity. Gaia simultaneously pushes both to awesome extremes. The instrumentation engineer in me is thrilled and amazed.

[ElvisTTBoy]

I spent quite a few years in a team developing the Proximity Electronics of the CCD Detectors for GAIA, trying to extract as much performance as possible to meet the requirements the scientists needed (the SNR requirements were crazy!). It's nice to see all the data coming out now and the scientists so busy with it!

[jacksoncrocker]

So glad you mentioned Issac! You two are some of my favorite channels out there 😊

[unvergebeneid]

All the ESA animations used in this video are mesmerizing and endlessly fascinating!

[c.augustin]

Yes, Isaac Arthur has many incredible videos on YouTube – but all are much longer than these much more dense PBS Space Time episodes here. If you have the time to watch, he's definitely worth a look!

[fullmetalpoitato]

Thanks for plugging Isaac Arthur's channel! PBS Spacetime and Isaac are my two favorite educational channels, it's good to see you guys giving each other kudos.

[fNktn]

I'm studying physics in Dresden and part of this mission was worked on here so I was lucky enough to allready hear this presentation (more or less) friday 2 weeks ago :D still nice video as allways though!

[SakurabaAyane]

I clicked on this because I thought it was about Gaia Hypothesis. This is much better.

[enhydralutra]

I always point towards Issac Arthur's channel whenever someone shows interest in writing science fiction.

[davethepak]

Exceptionally we done (Gaia AND PBS Space time for making this easy to follow). As an avid astronomy learner, I would love to see a full hour long episode/show on this topic.
thanks for the video.

[gokuldinesh]

Goosebumps!! It is nice to see the growth and I am super proud to live in this era! Wish I could contribute to the success one day!

[baumulrich]

giving isaac arthur a shoutout, just when i thought i couldnt love you guys more <3

[Frediloc]

WOAH. This is incredible. So many fantastic leaps in our level of understanding. I look forward to more to come from Gaia!

In the old times we needed to travel to improve our maps! It's amazing how we can now make such detailed 3D map of the Milky Way without leaving our tiny spot in our Solar System.

[animistchannel]

Isaac Arthur's channel is great -- science, engineering, speculation, and humor. Also, I loved the Bladerunner jokes at the end of this. I reference that saying too.

[mmxgn]

Isaac Arthur's Channel is also awesome. And kurzegsagt had the rotating black hole energy harvesting episode a while ago. I watch all three. Space, yay.

[paxromana]

I really appreciate the demonstration of parallax measurement using the animated constellations.

[tomduke]

wow! that was an unexpected massive treat! i actualy teared up a little, so much data! so happy right now!

[joeycook]

Absolutely brilliant episode. And I also strongly approve of, and am greatful for the love to Isaac Arthur's channel. Spacetime and IA's channels are my two favorites on YouTube (followed by several other PBS productions).I love the long format on IA's. Keep up the great work, Spacetime. Great work, Dr. O'Dowd.

[madnessbydesignVria]

As amazing as this is, I'm saddened that our 'leadership' continues failing to value scientific exploration. The rest of the world moves forward as we fall backwards. Thank you ESA!