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The second Gaia data release is scheduled to happen at Noon CEST tomorrow, 25 Apr 2018.
It'll include positions for 1,692,919,135 stars.
Information about Gaia is available at
http://sci.esa.int/gaia/
and about DR2 at
https://www.cosmos.esa.int/web/gaia/dr2
According to the DR2 Media Kit, which is available at
http://sci.esa.int/gaia/60174-media-kit-...release-2/
Quote:The press event about the Gaia Data Release 2 is being organised by ESA at
the ILA Berlin Air and Space Show in Germany on Wednesday 25 April 2018,
11:00–12:15 CEST.
The event will be streamed live at: http://www.esa.int/live
Note to moderators: Please feel free to move this elsewhere. I frustrated over which sub-forum might be appropriate.
Selden
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That's amazing. I wonder what the error bars will be like this time.
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(04-25-2018, 01:29 AM)stevebowers Wrote: That's amazing. I wonder what the error bars will be like this time.
Some preliminary estimates were published in November. See
https://arxiv.org/pdf/1710.10816
GAIA: ON THE ROAD TO DR2 Wrote:the preliminary values for the formal errors on the parallaxes are: 30
µas at G=15, 150 µas at G=18 and 700 µas at G=20.
where G "denotes the broad-band, white-light, Gaia magnitude."
Unfortunately, they also vary depending on where Gaia points on the sky.
More details are available at
https://www.cosmos.esa.int/web/gaia/science-performance
Selden
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I downloaded a high res version of the "all-sky-view" and I have to say, it doesn't have the wow factor of a nice desktop wallpaper.
My low-brow comment would be that it looks like a nice
opal at best.
Why the oblong oval shape?
I'm now wondering if there was a
Tissot's Indicatrix applied. I might have to try the VR version just to get past any 2D transformation distortions.
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What's the URL of the image you downloaded?
The map is oval because ESA uses the "Hammer" projection to translate the sky's spherical shape into flat images. This is documented at
https://www.cosmos.esa.int/web/gaia/gaia...kyincolour
They don't use Tissot's.
There are many different types of map projections. See
https://en.wikipedia.org/wiki/Map_projection
Celestia uses "Plate Carre" for its planetary maps, for example, which is also called "equirectangular".
Selden
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There's an interesting dark cloud just south of Sagittarius in that image
https://www.cosmos.esa.int/web/gaia/gaia...kyincolour
I think it is the Corona Australis molecular cloud. Only about 500 light years away. For some reason I find these dark clouds fascinating.
