Handy Gaia files for NYC Gaia Sprint
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* apass-dr9.fits -- https://www.aavso.org/apass -- an All-Sky
photometric survey, B,V,g,r,i, 60 million sources, ~7 to 17th mag.

* apass-dr9.fits.gz -- same, gzipped

'''
APASS is a public service to the astronomical community, and was
funded through generous contributions from the Robert Martin Ayers
Sciences Fund and the AAVSO endowment.  We have recently obtained an
NSF grant to complete the data analysis for the final catalog.  If you
use APASS for your research, please consider supporting the AAVSO with
your membership or a contribution.  You should also acknowledge APASS
with the following credit line: "This research was made possible
through the use of the AAVSO Photometric All-Sky Survey (APASS),
funded by the Robert Martin Ayers Sciences Fund."
'''

I got this by a nasty method:
http://tapvizier.u-strasbg.fr/TAPVizieR/
search for "select * from "II/336/apass9"
download as CSV (FITS format was broken when I tried)
convert to FITS, massage with this script:
https://github.com/dstndstn/gaia/blob/master/apass.py


* tgas-sources.fits -- Gaia Tycho-2-Gaia Astrometric Solution catalog,
  merged into one file, just by merging the publicly released Gaia DR1
  TGAS files.

* tgas-matched-2mass.fits.gz -- 2MASS matched (4" nearest neighbour),
  row-aligned (row 0 in tgas-matched-2mass.fits.gz is matched to row 0
  in tgas-sources.fits).  There is a "matched" column that says
  whether a match was found; unmatched rows have all zero values.  The
  "matchdist" column gives the matching distance (in degrees).
  http://irsa.ipac.caltech.edu/Missions/2mass.html

* tgas-matched-2mass-cut.fits -- same, with a subset of the columns.

* tgas-matched-wise.fits.gz -- WISE matched (4" nearest neighbour),
  from AllWISE release catalog.
  http://wise2.ipac.caltech.edu/docs/release/allwise/

* tgas-matched-wise-cut.fits -- same, with a subset of the columns.

* tgas-matched-apass-dr9.fits -- APASS DR9 matched (1" nearest
  neighbour), row-aligned with TGAS.


* tgas-sdss-match.fits -- match (1" nearest) between SDSS DR13
  spectroscopic objects and TGAS sources.  Unlike the "tgas-matched-*"
  files, this is not row-aligned, but rather contains all columns from
  both catalogs.  Only 2265 matches, in 26 distinct plates in
  different parts of the sky.

* decals-dr3-gaia.fits -- a match between DECaLS DR3 (g,r,z
  photometry) and the full 1-billion source Gaia catalog.  34 million
  matches.  DR3 is described at legacysurvey.org/dr3 ; since the survy
  is in-progress, different parts of the sky have different coverage,
  so not all has coverage in all of g,r,z bands to full depth.