The European Space Agency’s
Gaia spacecraft team has dropped its long-awaited trove of data about 1.7
billion stars. You can see a new visualization of all those stars in the Milky
Way and nearby galaxies above, but you really need to zoom in to appreciate
just how much stuff there is in the map. Yes, the specks are stars.
In addition to the 1.7
billion stars, this second release of data from Gaia contains the motions and
color of 1.3 billion stars relative to the Sun, as well as how the stars relate
to things in the distant background based on the Earth’s position. It also
features radial velocities, amount of dust, and surface temperatures of lots of
stars, and a catalogue of over 14,000 Solar System objects, including
asteroids. There is a shitload of data in this release.
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“Only time will tell what astronomers will make of this,” Gaia Science Operations Manager Uwe Lammers told Gizmodo.
And astronomers are already
making something of it. Ronald Drimmel, astronomer at the Turin Astrophysical
Observatory, posted this map of stars’ positions and their velocities. Our
galaxy’s spiral arms have begun to emerge out of the data.
The ESA has also posted a
number of other data visualizations. Here are the trajectories of almost 90
Milky Way satellites, including clumps of stars called globular clusters in
blue, and orbiting galaxies in red. You can see the famous Large and Small
Magellanic Clouds on the bottom right. And here are the orbits of the Solar
System objects around the sun, colored based on their brightness.
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| Map of the Milky Way containing its satellites. Image: ESA |
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| Asteroids around the Sun based on brightness Image: ESA |
This is of course the very,
very beginning. Scientists hoping to understand our galaxy will still need to
sift through, analyze, and crunch all this data in order to discover more about
the universe. This will take years. Once they’ve done that, it’s on to Gaia
data release three, scheduled for the 2020s. Gaia launched in 2013 and orbits
the sun at the same rate as Earth, though it’s about 1.5 million kilometers
farther away.
The link to the data
is here,
and a guide for what the data contains and how to use it here. There’s
also a crapton more layperson-facing stuff here. Enjoy!