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New Gaia data release tracks distance and motion of 1.8 billion stars

The European Space Agency (ESA) today released the third round of data from its Gaia satellite, designed to measure precisely the distance and motion of billions of nearby stars.

Gaia EDR3 contains detailed information on more than 1.8 billion sources, detected by the Gaia spacecraft. This represents an increase of more than 100 million sources over the previous data release (Gaia DR2), which was made public in April 2018. Gaia EDR3 also contains colour information for around 1.5 billion sources, an increase of about 200 million sources over Gaia DR2. As well as including more sources, the general accuracy and precision of the measurements has also improved.

This release also included the following discoveries:

  • The Milky Way’s outer regions beyond the Sun contain two populations of stars, one slowly dropping towards the galaxy’s plane, the second flying away quickly.
  • The first precise measure of the solar system’s orbit in the Milky Way
  • A more complete census of all stars within 100 parsecs of the Sun
  • A better map of the interaction between the Large Magellanic Cloud and the Milky Way, which also showed that the cloud does have a spiral structure

This precise data will take decades to digest, as past research has been based on only rough distance and motion estimates. Having precise data will change our approximation of each object’s brightness, which will also change much of what we assume about it.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

One comment

  • LocalFluff

    The third data release will surely be dug into by those who hunt exoplanets. Of course only a fraction of stars have planetary discs aligned with our line of sight. And a small fraction of them happen to have been repeatedly transiting each time Gaia briefly but repeatedly looked at them. But a billion multiplied by one-in-a-million is still many. Gaia might swamp Kepler in terms of number of exoplanets discovered during next year.

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