<p>It seems a bunch of people, including myself, have got it into our heads to create a 3D visualisation of the stars around us - one where you get to fly around them rather than view them from the viewpoint of Earth.</p>

<p>This means, obviously, that I'm limited to stars that have parallax values, which in the case of the <a href="https://gea.esac.esa.int/archive/" rel="nofollow noreferrer">Gaia archive</a> is about 2 million whereas in <a href="http://simbad.u-strasbg.fr/simbad/" rel="nofollow noreferrer">Simbad</a> 100 000. The reason why I'd like to use both is that Simbad appears to have more useful information, including names and types of star. Also, amazingly, the highest parallax (in milliarcseconds) in gaia is in the 200s, which suggests that alpha centauri is not in the archive! My hunch is that Simbad is the place to go for nearby and named stars, whereas Gaia has higher numbers.</p>

<p>I imagine (perhaps incorrectly) that there is a way to identify a Simbad star on the Gaia database and vice versa. Gaia has a bunch of id values (solution_id, source_id, random_index) whereas on Simbad there's just the one (Identifier). I have the suspicion that Simbad may have more columns I'm not aware of.</p>

<p>In any case, my plan would be to query both archives, and weed out multiples based on an identifier of some sort. Maybe there's a third database that links the two? Maybe I'm missing something obvious? Perhaps there's the perfect page out there that tells me precisely how to do this which has eluded my googling.</p>

<p>Any help would be greatly appreciated.</p>

CC BY-SA 3.0
2017-02-16T11:04:22.773Z
You need to start by learning more about what is in the TGAS catalogue and what isn't - it is not a "complete" catalogue in any sense. It is no surprise to find a very bright star like Alpha Cen missing. The "identifier" that you need is the coordinates of the star!
ProfRob
CC BY-SA 3.0
2017-02-16T13:00:31.507Z
The 100.000 stars from the simbad catalogue in the end come from the Hipparcos catalogue/mission, which are the same stars that Gaia is looking at (and more, ofc). Gaia however intentionally misses out on very bright stars in their data releases, as they don't know yet how to treat those super-saturating stars in their astrometric solution. Details: http://www.aanda.org/articles/aa/full_html/2016/11/aa29512-16/aa29512-16.html
AtmosphericPrisonEscape
CC BY-SA 3.0
2017-02-16T23:05:36.993Z
Thanks to both of you for your insights. I was worried that the coordinates might not necessarily match because of precision errors, and as such could not be used as a reliable identifier, though some testing seems to indicate it's ok. As for the idea the Gaia does not include data for extra bright stars, that is exactly the kind of insight that I came to this site for! Reading up on it, I see the sense of it, but I've come to this project as a programmer, not an astronomer, so that was not an immediately obvious avenue. Thanks so much!
Awoogamuffin
CC BY-SA 4.0
2022-04-14T16:19:57.583Z
Thanks for this question and for the comments. I'm wondering what an up-do-date answer would be, given the availability of Gaia DR2 and even EDR3.  E.g. @ProfRob, I read that *The Tycho-Gaia Astrometric Solution (TGAS) is specific to Gaia DR1 and will not be used in future releases.*
nealmcb
<gaia>
A question about using both the Simbad and the Gaia archive
Awoogamuffin
# A question about using both the Simbad and the Gaia archive

(Asked by: username_0 on 2017-02-15)

It seems a bunch of people, including myself, have got it into our heads to create a 3D visualisation of the stars around us - one where you get to fly around them rather than view them from the viewpoint of Earth.

This means, obviously, that I'm limited to stars that have parallax values, which in the case of the [Gaia archive](https://gea.esac.esa.int/archive/) is about 2 million whereas in [Simbad](http://simbad.u-strasbg.fr/simbad/) 100 000. The reason why I'd like to use both is that Simbad appears to have more useful information, including names and types of star. Also, amazingly, the highest parallax (in milliarcseconds) in gaia is in the 200s, which suggests that alpha centauri is not in the archive! My hunch is that Simbad is the place to go for nearby and named stars, whereas Gaia has higher numbers.

I imagine (perhaps incorrectly) that there is a way to identify a Simbad star on the Gaia database and vice versa. Gaia has a bunch of id values (solution\_id, source\_id, random\_index) whereas on Simbad there's just the one (Identifier). I have the suspicion that Simbad may have more columns I'm not aware of.

In any case, my plan would be to query both archives, and weed out multiples based on an identifier of some sort. Maybe there's a third database that links the two? Maybe I'm missing something obvious? Perhaps there's the perfect page out there that tells me precisely how to do this which has eluded my googling.

Any help would be greatly appreciated.

**Tags:** gaia
> **Comments:**
> **username_1**: You need to start by learning more about what is in the TGAS catalogue and what isn't - it is not a "complete" catalogue in any sense. It is no surprise to find a very bright star like Alpha Cen missing. The "identifier" that you need is the coordinates of the star!  
> **username_2**: The 100.000 stars from the simbad catalogue in the end come from the Hipparcos catalogue/mission, which are the same stars that Gaia is looking at (and more, ofc). Gaia however intentionally misses out on very bright stars in their data releases, as they don't know yet how to treat those super-saturating stars in their astrometric solution. Details: http://www.aanda.org/articles/aa/full_html/2016/11/aa29512-16/aa29512-16.html  
> **username_0**: Thanks to both of you for your insights. I was worried that the coordinates might not necessarily match because of precision errors, and as such could not be used as a reliable identifier, though some testing seems to indicate it's ok. As for the idea the Gaia does not include data for extra bright stars, that is exactly the kind of insight that I came to this site for! Reading up on it, I see the sense of it, but I've come to this project as a programmer, not an astronomer, so that was not an immediately obvious avenue. Thanks so much!  
> **username_3**: Thanks for this question and for the comments. I'm wondering what an up-do-date answer would be, given the availability of Gaia DR2 and even EDR3.  E.g. @ProfRob, I read that *The Tycho-Gaia Astrometric Solution (TGAS) is specific to Gaia DR1 and will not be used in future releases.*  

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## 0 answers

