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Astronomers have just gotten a brand-new view of our home galaxy, the Milky Way. That's because early this morning, the European Space Agency released an astounding new star map. Scientists immediately started studying it, and they're already making new discoveries. NPR's Nell Greenfieldboyce joined one group of researchers in New York City.
NELL GREENFIELDBOYCE, BYLINE: David Hogg got up before 5 a.m. this morning because he was so excited that today was the day he was going to get precise measurements on 1.7 billion stars.
DAVID HOGG: So for me, it's potentially, really, a life-changing event.
GREENFIELDBOYCE: He's an astrophysicist at New York University. The data he was waiting for comes from a European science mission called Gaia. Gaia is a spacecraft that's orbiting the sun about a million miles from Earth, charting the brightness, motion, color and position of an unprecedented number of stars in our galaxy.
HOGG: We're really talking about an immense change to our knowledge about the Milky Way.
GREENFIELDBOYCE: And the Gaia team was going to release all of this to the public all at once. So Hogg invited dozens of colleagues to join him at the Flatiron Institute in Manhattan. They gathered in a conference room before dawn, watching a live broadcast from Europe as the mission's scientists showed off some of the first images made with the new data.
UNIDENTIFIED SCIENTISTS: Whoa.
GREENFIELDBOYCE: Then Andy Casey from Monash University noticed something.
ANDY CASEY: You can download it already. It's out early.
GREENFIELDBOYCE: He found a way to get the data a few minutes before the official release time. Heads bent over laptops. People started looking at everything from white dwarfs to cosmic dust. Keith Hawkins is from Columbia University. He was looking for hypervelocity stars, stars moving super-fast. Only about 20 had been known, and he quickly used the Gaia data to discover one more.
KEITH HAWKINS: It's a completely new hypervelocity star. I haven't looked anything further - other than its velocity. It's moving at about 600 kilometers per second, which is enormously fast - on the order of - a few million miles per hour, at least.
GREENFIELDBOYCE: How do you feel? Yeah. I mean, there's only 20. So what is it like to find another one?
HAWKINS: Feels good. There's one new one, so I suspect we'll see thousands of new ones discovered within the next few hours.
GREENFIELDBOYCE: Meanwhile, others we're finding weird, unexpected stuff. Adrian Price-Whelan is from Princeton University.
ADRIAN PRICE-WHELAN: I'm sitting here with Ana Bonaca, who's a post-doc at Harvard, and we've been looking at the Gaia data for this stellar stream.
GREENFIELDBOYCE: It's like a stream of moving stars. And what they saw were signs that stars had been forced out of the stream in an odd way.
PRICE-WHELAN: Which could be an indication of an interaction with a dark matter subhalo, which has been never before seen.
GREENFIELDBOYCE: That would be a big deal if it's true.
PRICE-WHELAN: But it's probably wrong (laughter).
GREENFIELDBOYCE: This scene was being repeated all around the world. The European Space Agency said that within the first three hours, the new information had been accessed by more than 4,000 people.
JACKIE FAHERTY: It's exciting to be around each other and trying to get the data all at once.
GREENFIELDBOYCE: Jackie Faherty is an astronomer at the American Museum of Natural History.
FAHERTY: This is the data we're going to be working on for the rest of my career. Probably no data set will rival this.
GREENFIELDBOYCE: She says this is just the first day of what will be years of research, but it's a day they'll always remember. Nell Greenfieldboyce, NPR News.
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