Create directory for auxiliary output files

.gitignore

@@ -1,6 +1,12 @@
 # Downloaded catalogs and output files
+/auxfiles/*
+!/auxfiles/CREDITS.md
+!/auxfiles/LICENSE.txt
+!/auxfiles/hip2dist.csv
 /data
-/output/*.dat
+/output/*
+!/output/CREDITS.md
+!/output/LICENSE.txt
 /celestia*.zip
 
 # Python cache and virtual environment

auxfiles/CREDITS.md

@@ -0,0 +1,171 @@
+# Credits
+
+These files were generated with the celestia-gaia-stardb application available
+at https://github.com/ajtribick/celestia-gaia-stardb.
+
+## References
+
+### Source catalogues
+
+- *Gaia* Early Data Release 3 (https://gea.esac.esa.int/archive/)
+    - *Gaia* Collaboration et al. (2016), A&A 595, id.A1, "The *Gaia* mission"
+    - *Gaia* Collaboration et al. (2021), A&A 649, id.A1, "*Gaia* Early Data
+      Release 3. Summary of the contents and survey properties"
+    - *Gaia* Collaboration et al. (2021), A&A forthcoming, "Erratum: *Gaia*
+      Early Data Release 3. Summary of the contents and survey properties"
+    - Lindegren et al. (2021), A&A 649, id.A2, "*Gaia* Early Data Relese 3.
+      The astrometric solution"
+    - Riello et al. (2021), A&A 649. id.A3, "*Gaia* Early Data Release 3.
+      Photometric content and validation"
+
+- Bailer-Jones et al. (2021), AJ 161(3), id.147 "Estimating Distances from
+  Parallaxes. V. Geometric and Photogeometric Distances to 1.47 Billion Stars
+  in Gaia Early Data Release 3"
+
+- Extended Hipparcos Compilation (XHIP)
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/V/137D)
+
+  Anderson & Francis (2012), AstL 38(5), pp.331–346 "XHIP: An extended
+  Hipparcos compilation"
+
+- ASCC-2.5, 3rd version (http://cdsarc.u-strasbg.fr/viz-bin/cat/I/280B)
+
+  Kharchenko (2001), Kinematika i Fizika Nebesnykh Tel 17(5), pp.409-423
+  "All-sky compiled catalogue of 2.5 million stars"
+
+- HD identifications for Tycho-2 stars
+  (https://cdsarc.unistra.fr/viz-bin/cat/IV/25)
+
+  Fabricius et al. (2002), A&A 386, pp.709–710 "Henry Draper catalogue
+  identifications for Tycho-2 stars"
+
+- Teff and metallicities for Tycho-2 stars
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/V/136)
+
+  Ammons et al. (2006), ApJ 638(2), pp.1004–1017 "The N2K Consortium. IV. New
+  Temperatures and Metallicities for More than 100,000 FGK Dwarfs"
+
+- The Tycho-2 Spectral Type Catalog
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/III/231)
+
+  Wright et al. (2003), AJ 125(1), pp.359–363 "The Tycho-2 Spectral Type
+  Catalog"
+
+- New spectral types for Tycho2 stars
+  (https://cdsarc.unistra.fr/viz-bin/cat/J/PAZh/34/21)
+
+  Tsvetkov et al. (2008), Astronomy Letters 34(1), pp.17–27 "Inaccuracies in
+  the spectral classification of stars from the Tycho-2 Spectral Type
+  Catalogue"
+
+- SAO Star Catalog J2000 (http://cdsarc.u-strasbg.fr/viz-bin/cat/I/131A)
+
+  SAO Staff, "Smithsonian Astrophysical Observatory Star Catalog (1990)"
+
+### Source catalogues used in earlier versions
+
+- *Gaia* Data Release 2 (https://gea.esac.esa.int/archive/)
+    - *Gaia* Collaboration et al. (2016), A&A 595, id.A1, "The *Gaia* mission"
+    - *Gaia* Collaboration et al. (2018), A&A 616, id.A1, "*Gaia* Data
+      Release 2. Summary of the contents and survey properties"
+    - Andrae et al. (2018), A&A 616, id.A8, "*Gaia* Data Release 2. First
+      stellar parameters from Apsis"
+    - Evans et al. (2018), A&A 616, id.A4 "*Gaia Data Release 2. Photometric
+      content and validation"
+    - Marrese et al. (2018), A&A 621, id.A144, "*Gaia* Data Release 2.
+      Cross-match with external catalogues: algorithms and results"
+
+- *Gaia* Data Release 2 Geometric Distances
+  (http://www.mpia.de/~calj/gdr2_distances/main.html)
+
+  Bailer-Jones et al. (2018), AJ 156(2), id.58 "Estimating Distance from
+  Parallaxes. IV. Distances to 1.33 Billion Stars in *Gaia* Data Release 2"
+
+- Binarity of Hipparcos stars from Gaia pm anomaly
+  (https://cdsarc.unistra.fr/viz-bin/cat/J/A%2bA/623/A72)
+
+  Kervella et al. (2019), A&A 623, id.A72 "Stellar and substellar companions
+  of nearby stars from Gaia DR2. Binarity from proper motion anomaly"
+
+### Additional catalogues of interest
+
+- The Hipparcos and Tycho Catalogues (1997)
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/I/239)
+  - Perryman et al. (1997), A&A 500 pp.501–504 "The Hipparcos Catalogue"
+  - Høg et al. (1997), A&A 323 pp.L57–L60 "The TYCHO Catalogue"
+
+- Hipparcos, the New Reduction (http://cdsarc.u-strasbg.fr/viz-bin/cat/I/311)
+
+  van Leeuwen (2007), A&A 474(2) pp.653–664 "Validation of the new Hipparcos
+  reduction"
+
+- The Tycho-2 Catalogue (http://cdsarc.u-strasbg.fr/viz-bin/cat/I/259)
+
+  Høg et al. (2000), A&A 355 pp.L27–L30 "The Tycho-2 catalogue of the 2.5
+  million brightest stars"
+
+- Henry Draper Catalogue and Extension
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/III/135A)
+
+  Cannon & Pickering (1918–1924), Annals of the Astronomical Observatory of
+  Harvard College
+
+### Data processing
+
+- UBVRIJHK color-temperature calibration
+  (http://cdsarc.u-strasbg.fr/viz-bin/cat/J/ApJS/193/1)
+
+  Worthey & Lee (2011), ApJS, 193(1), id.1 "An Empirical UBV RI JHK
+  Color-Temperature Calibration for Stars"
+
+- Bailer-Jones (2015), PASP 127(956), pp.994 "Estimating Distances from
+  Parallaxes"
+
+- Astraatmadja & Bailer-Jones (2016), ApJ 833(1), id.119 "Estimating
+  Distances from Parallaxes. III. Distances of Two Million Stars in the
+  *Gaia* DR1 Catalogue"
+
+- Oliphant (2006), USA: Trelgol Publishing "A guide to NumPy"
+
+- van der Walt et al. (2011), Computing in Science & Engineering, 13, 22–30
+  "The NumPy Array: A Structure for Efficient Numerical Computation"
+
+- Harris et al. (2020), Nature 585, 357–362 "Array programming with NumPy"
+
+- Astropy Collaboration et al. (2013), A&A 558, id.A33 "Astropy: A community
+  Python package for astronomy"
+
+- Astropy Collaboration et al. (2018), AJ 156(3), id.123 "The Astropy Project:
+  Building an Open-science Project and Status of the v2.0 Core Package"
+
+- Brandt (2018), ApJSS 239(2), id.31 "The *Hipparcos*-*Gaia* Catalog of
+  Accelerations"
+
+### Databases
+
+- Wenger et al. (2000), A&A 143, 9–22 "The SIMBAD astronomical database. The
+  CDS reference database for astronomical objects"
+
+- Ochsenbein et al. (2000), A&AS 143, 23–32 "The VizieR database of
+  astronomical catalogues"
+
+## Acknowledgements
+
+This work has made use of data from the European Space Agency (ESA) mission
+*Gaia* (https://www.cosmos.esa.int/gaia), processed by the *Gaia* Data
+Processing and Analysis Consortium (DPAC,
+https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has
+been provided by national institutions, in particular the institutions
+participating in the *Gaia* Multilateral Agreement.
+
+This work has made use of the SIMBAD database, operated at CDS, Strasbourg,
+France.
+
+This work has made use of the VizieR catalogue access tool, CDS, Strasbourg,
+France (DOI : 10.26093/cds/vizier). The original description of the VizieR
+service was published in 2000, A&AS 143, 23.
+
+This work made use of the cross-match service provided by CDS, Strasbourg.
+
+This work made use of [Astropy](http://www.astropy.org), a community-developed
+core Python package for Astronomy.