<p>Perhaps I am late, but the GCNS is available via <em>VizieR</em>. The data can be both queried there and downloaded via FTP: <a href="https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/649/A6#/browse" rel="nofollow noreferrer">https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/649/A6#/browse</a>, theoretically it is also available via the Gaia-Archive (<a href="https://www.cosmos.esa.int/web/gaia/" rel="nofollow noreferrer">https://www.cosmos.esa.int/web/gaia/</a>), at least according to an announcement dating 21/12/2021, but I did not manage to find the actual data. Anyway, I'm not sure whether you will find what you need solely based on the data in the GCNS.</p>

CC BY-SA 4.0
2022-01-18T02:12:59.780Z
That looks like what I was looking for. OTOH whoever put that up seems to have botched the filenames, to say the least. The most relevant file `J_A+A_649_A6_table1c.dat.gz.txt.gz`, despite saying `.gz` *twice* is in fact uncompressed text.
BCS
CC BY-SA 4.0
2022-01-16T16:22:08.273Z
2022-01-16T16:22:08.273Z
CR131873
<p>If you want to find the common star names for the stars in Gaia Catalogue of Nearby Stars - GCNS : J/A+A/649/A6 described above you can pen the file in TOPCAT and then do a cross match on the Simbad Server using TOPCATs built in X-Match interface to CDS.</p>
<p>However it may be better to filter the stars first to remove ones fainter than you are interested in - the number of stars more than doubles with each magnitude. The other thing to be aware of is that the Gaia data is incomplete for bright stars due to problems determining the centroid of the bright image.</p>
<p>The data table above also contains quite a number of stars shown with a G Mag of zero - which seems to be used where there is no data.</p>
<p>You can also use TOPCAT to save the data that was in FITS format into .CSV or other formats but beware of the information loss.</p>
<p>Depending on what you want to do there are lots of functions in TOPCAT that make life easy handling astronomical data. It can produce some pretty good plots as well.</p>

CC BY-SA 4.0
2022-03-01T09:08:40.010Z
2022-03-01T09:08:40.010Z
John
<p>Has Gaia made the &quot;Gaia Catalog of Nearby Stars&quot; (GCNS) available for offline processing?</p>
<p>Ideally I'd like the full 100pc data set in a format that doesn't require any specialized libraries to parse, e.g. something like CSV.</p>
<p>I've found a pile of papers talking about work done with that data, and I think I've found a download link to a larger (~TiB) data set, as well as some online search tools (that are poorly documented and hard to use unless you already know how) but I've had no luck finding a copy of the 100pc GCNS.</p>
<hr />
<p>Alternatively: all I really need is 3D location (however described), spectral class and (ideally) masses for bodes larger than brown dwarfs. Are there any other catalogs that have near complete data for that out to ~100pc that are readily available for off line processing?</p>

CC BY-SA 4.0
2021-12-30T22:33:43.707Z
You stand a better chance with the HIPPARCOS data. The dataset from the GAIA mission is huge and would take an enormous amount of time to download, plus consumer-level computers might have a hard time accessing it because it’s so large—actually, it’s broken in chunks, but a quick look at them reveals that even the chunks are huge! HIPPARCOS, on the other hand, is a smaller dataset. I’m not sure how complete it is, but for stars within 100 pc, I’m sure it’s good enough.
Pierre Paquette
CC BY-SA 4.0
2021-12-30T23:03:04.440Z
Interesting. From what references I can find, the GCNS is only about 300k objects to avoid those exact issues. HIPPARCOS does have the advantage of being easy to *find*, but seems to only have around 118k objects. -- Do you know of a source for mapping that data to common names?
BCS
CC BY-SA 4.0
2021-12-30T23:17:57.080Z
Most stars don’t have “common names,” but your best source would be the International Astronomical Union’s page: https://www.iau.org/public/themes/naming_stars/ as well as maybe Wikipedia.
Pierre Paquette
CC BY-SA 4.0
2021-12-30T23:50:23.457Z
@PierrePaquette I'm sure you are correct, but I also suspect the majority of the ones that do are in the set of stars I'm looking for data on. Also, in my use-case, dealing with named stars we eventual be a major requirement.
BCS
CC BY-SA 4.0
2021-12-31T00:27:29.557Z
@PierrePaquette Also, doing a rather course test, HIPPARCOS seems to be somewhat incomplete even inside of ~100pc. I may or may not be able to live with that. TBD. I plotted running sums of stars by class, which should at least approximate $O(r^3)$. Plotted log-log, D and M class quickly fall off around 30pc with K and G following at about 50pc and 80pc respectively. See: https://docs.google.com/spreadsheets/d/1dNfwcNanrOmrnWe5rGBFZ9DaEjmiiROrn02yVyCtdP0/edit?usp=sharing
BCS
<data-analysis><gaia><star-catalogues><raw-data>
Downloadable GCNS (Gaia Catalog of Nearby Stars)
BCS
# Downloadable GCNS (Gaia Catalog of Nearby Stars)

(Asked by: username_0 on 2021-12-30)

Has Gaia made the "Gaia Catalog of Nearby Stars" (GCNS) available for offline processing?

Ideally I'd like the full 100pc data set in a format that doesn't require any specialized libraries to parse, e.g. something like CSV.

I've found a pile of papers talking about work done with that data, and I think I've found a download link to a larger (~TiB) data set, as well as some online search tools (that are poorly documented and hard to use unless you already know how) but I've had no luck finding a copy of the 100pc GCNS.

---

Alternatively: all I really need is 3D location (however described), spectral class and (ideally) masses for bodes larger than brown dwarfs. Are there any other catalogs that have near complete data for that out to ~100pc that are readily available for off line processing?

**Tags:** data-analysis, gaia, star-catalogues, raw-data

> **Comments:**
> **username_1**: You stand a better chance with the HIPPARCOS data. The dataset from the GAIA mission is huge and would take an enormous amount of time to download, plus consumer-level computers might have a hard time accessing it because it’s so large—actually, it’s broken in chunks, but a quick look at them reveals that even the chunks are huge! HIPPARCOS, on the other hand, is a smaller dataset. I’m not sure how complete it is, but for stars within 100 pc, I’m sure it’s good enough.  
> **username_0**: Interesting. From what references I can find, the GCNS is only about 300k objects to avoid those exact issues. HIPPARCOS does have the advantage of being easy to *find*, but seems to only have around 118k objects. -- Do you know of a source for mapping that data to common names?  
> **username_1**: Most stars don’t have “common names,” but your best source would be the International Astronomical Union’s page: https://www.iau.org/public/themes/naming_stars/ as well as maybe Wikipedia.  
> **username_0**: @PierrePaquette I'm sure you are correct, but I also suspect the majority of the ones that do are in the set of stars I'm looking for data on. Also, in my use-case, dealing with named stars we eventual be a major requirement.  
> **username_0**: @PierrePaquette Also, doing a rather course test, HIPPARCOS seems to be somewhat incomplete even inside of ~100pc. I may or may not be able to live with that. TBD. I plotted running sums of stars by class, which should at least approximate $O(r^3)$. Plotted log-log, D and M class quickly fall off around 30pc with K and G following at about 50pc and 80pc respectively. See: https://docs.google.com/spreadsheets/d/1dNfwcNanrOmrnWe5rGBFZ9DaEjmiiROrn02yVyCtdP0/edit?usp=sharing  

---

## 2 answers

### Answer by username_2 on 2022-01-16. Score: 3 | Accepted answer

Perhaps I am late, but the GCNS is available via *VizieR*. The data can be both queried there and downloaded via FTP: <https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/649/A6#/browse>, theoretically it is also available via the Gaia-Archive (<https://www.cosmos.esa.int/web/gaia/>), at least according to an announcement dating 21/12/2021, but I did not manage to find the actual data. Anyway, I'm not sure whether you will find what you need solely based on the data in the GCNS.

> **Comments:**
> **username_0**: That looks like what I was looking for. OTOH whoever put that up seems to have botched the filenames, to say the least. The most relevant file `J_A+A_649_A6_table1c.dat.gz.txt.gz`, despite saying `.gz` *twice* is in fact uncompressed text.  

---

### Answer by username_3 on 2022-03-01. Score: 1

If you want to find the common star names for the stars in Gaia Catalogue of Nearby Stars - GCNS : J/A+A/649/A6 described above you can pen the file in TOPCAT and then do a cross match on the Simbad Server using TOPCATs built in X-Match interface to CDS.

However it may be better to filter the stars first to remove ones fainter than you are interested in - the number of stars more than doubles with each magnitude. The other thing to be aware of is that the Gaia data is incomplete for bright stars due to problems determining the centroid of the bright image.

The data table above also contains quite a number of stars shown with a G Mag of zero - which seems to be used where there is no data.

You can also use TOPCAT to save the data that was in FITS format into .CSV or other formats but beware of the information loss.

Depending on what you want to do there are lots of functions in TOPCAT that make life easy handling astronomical data. It can produce some pretty good plots as well.


---

