## Where can I find a catalog of all stars in the Milky Way?

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Is there a catalog of all known stars or brightest stars in our galaxy? Preferably with some sort of galactic coordinates instead of just night sky coordinates (right ascension, etc.) I'm trying to make a model of the milky way, explorable with an oculus rift.

– barrycarter – 2015-07-23T01:34:31.757

@self He says, "known stars". It implies catalogued. Otherwise, you got a point – Cheeku – 2014-06-13T04:05:11.270

What's the process like for cataloguing? Can we just go through celestial images taken from two locations, mark the stars and triangulate? Is this something that could potentially farmed out to Mechanial Turk? – Axiverse – 2014-06-13T06:35:48.233

@Cheeku I missed that. :( – this – 2014-06-13T14:05:03.653

@Axiverse Hard code the most known stars, and randomly/procedurally generate the rest. I hope to play you game someday. – this – 2014-06-13T14:07:05.540

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Hipparcos, the predecessor to Gaia, has a dataset (http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/239) with 3D positions for 100,000 stars. While we have much larger datasets of galactic stars, such as SDSS, finding the distances to stars is much harder. Parallax is the most precise technique for finding distances. Even for Gaia, we will only be able to measure distances to 10% precisions.

There is a "galactic coordinate system", but that stil has the sun at the center and the line between the sun and the galactic center as its reference. There are calculators that can convert RA and Dec to galactic coordinates (e.g. http://python4astronomers.github.io/astropy/coordinates.html). You can use that and the distance to place them in space.

It should be noted that any such catalog does not contain all stars in the galaxy. That would be impossible at the moment. However, existing catalogs represent best current efforts - so, in a way, that is the answer to the OP. – Florin Andrei – 2014-06-16T18:48:57.250

The 10% number for Gaia is incorrect. – Rob Jeffries – 2014-12-18T20:25:51.923

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No, such a catalogues does not (yet) exist. There are two reasons.

1 The Milky Way galaxy is about 20kpc (1pc ~= 3 lyr) across and only the very brightest stars are individually identifyable across such large a distance (such bright stars by their nature are very massive and hence young). Astronomers tend to cataloge stars by their apparent brightness, which for stars of identical luminosity declines as $1/d^2$ ($d$=distance). As a consequence, most catalogues contain only stars in the immediate galactic neighbourhood of the Sun. The Hipparcos catalogue (mentioned in another answer), for example, has most stars within a mere 100pc of the Sun.

2 Obtaining distances for individual stars is inherently difficult, in particular the more distant the star in question is. Accurate distances for stare several kpc away can currently only be obtained by indirect methods applicable only to certain types of stars (such as RR Lyrae variables). The classical trigonometric parallax measurement for such distances, however, is subject of ESA's ongoing Gaia mission.

ESA's Gaia satellite launched last year aims at cataloguing about $10^9$ stars across the Milky Way, including their velocity. The first preliminary versions of resulting catalogue, however, will still take some time to appear.

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My understanding is that any star catalog today represents only such a very tiny and local part of the Milky Way, that you would have very little use of it for your purpose.

In a year or two the Gaia space telescope will have mapped the one billion or 1% of the nearest and brightest stars in the Milky Way. Even then, to model a galaxy one needs other ideas than maps of individual stars.

Actually, more like beginning of 2017. – Rob Jeffries – 2015-10-12T23:44:19.463

Is there a way to actively track Gaia's progress as they are mapping stars one by one? – Axiverse – 2014-06-13T06:57:07.560

It seems that their first data release will be 22 months into the mission - so around end of 2015. Here's the link, still looking for a mailing list or intermediate data. Data Release Scenario

– Axiverse – 2014-06-13T07:12:06.873

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Gaia Data release is out (1 & 2).

If the kink is dead or you want more: can just type Gaia archive on a search engine and then go to downloads and you should find what you are searching for. You can also select only the ones that also have the radial velocities if you want to include time evolution.

For more precise requests, you can register to gaia archive (just need email adress + name and takes 5 minutes) and you can then do Queries to the database allowing you to filter the sources as you please.

Note:
1. The distances measurement have about 10% of error but it should be the state of the art for the moment being.
2. There are plenty of parameters more than just the astronomic parameters (position and velocity), that you can use for rendering your application as accurate and interesting as you like.

Gaia does not measure all the stars in the galaxy, as has been pointed out in other answers. The distances aren't just accurate to 10%, it is much more complicated than that. – Rob Jeffries – 2018-11-28T11:54:27.747

@RobJeffries you are indeed right, it is not all the stars in the galaxy but a good number considered the desired application. To my knowledge it is one of the best catalogue for doing what Axyverse wanted to achieve. You are right also for the error, it is much more complicated, depending on the characteristics of the star (e.g. how much it moves, or its change in colour that Gaia doesn't take into account to my knowledge), but the 10% is to give a approximative idea, since I guess for an VR application I am not sure how much exactitude is needed and a global idea might be sufficient. – alaka – 2018-11-28T14:23:52.847

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Galaxy Map has detailed information on 5000+ stars.