TGAS data was helpfully produced and given to us by Grégory Mantelet in
the form of a FITS file, 2016-09.  We pulled the file and the metadata
from http://gaia.ari.uni-heidelberg.de:8181/tgas/gaiadr1_tgas.fits
-- that was a test site at this point.

The metadata we actually got doing

curl -o meta.vot -FLANG=ADQL -FREQUEST=doQuery \
	-FQUERY="select top 1 * from gaiadr1.tgas_source" \
	http://gaia.ari.uni-heidelberg.de/tap/sync