Estimated distances to 1.33 billion stars in Gaia DR2
Short Name:
gdr2dist scs
Date:
04 Apr 2022 15:48:41
Publisher:
The GAVO DC team
Description:
This catalogue provides distances estimates (and uncertainties therein)
for 1.33 billion stars over the whole sky brighter than about G=20.7.
These have been estimated using the parallaxes (and their uncertainties)
from Gaia DR2. A Bayesian procedure was used involving a prior
with a single parameter L(l,b), which varies smoothly with Galactic
longitude and latitude according to a Galaxy model. The posterior is
summarized with a point estimate (usually the mode) and a confidence
interval (usually the 68% highest density interval). The estimation
procedure is described in detail in the `accompanying paper`_,
which also analyses the catalogue content.
.. _accompanying paper: http://www.mpia.de/homes/calj/gdr2_distances.html
This service returns the most important Gaia DR3 gaia_source columns
together with robust geometric and photogeometric distances for the
~1.47 billion objects in Bailer-Jones et al's distance catalogue.
The LIFE Target Star Database contains information useful
for the planned `LIFE mission`_ (mid-ir, nulling
interferometer in space). It characterizes possible
target systems including information about stellar,
planetary and disk properties. The data itself is mainly
a collection from different other catalogs.
Note that LIFE's target database is living
data. The content – and to some extent even structure – of these
tables may change at any time without prior warning.
.. _LIFE mission: https://life-space-mission.com/
This catalog combines Gaia DR1, Pan-STARRS 1, SDSS and 2MASS astrometry
to compute proper motions for 350 million sources across three-fourths of
the sky down to a magnitude of mr≈20. Positions of galaxies from Pan-STARRS 1
are used to build a reference frame for PS1, SDSS, and 2MASS data.
Gaia DR1 is adapted to that reference frame by exploiting that locally,
proper motions are linear.
GPS1 has a characteristic systematic error of less than 0.3 mas/yr, and
a typical precision of 1.5−2.0 mas/yr. The proper motions have been
validated using galaxies, open clusters, distant giant stars and QSOs. In
comparison with other published faint proper motion catalogs, GPS1's
systematic error (<0.3 mas/yr) is about 10 times better than that of PPMXL
and UCAC4 (>2.0 mas/yr). Similarly, its precision (~1.5 mas/yr) is
an improvement by ∼ 4 times relative to PPMXL and UCAC4 (∼6.0 mas/yr).
For QSOs, the precision of GPS1 is found to be worse (∼2.0−3.0 mas/yr),
possibly due to their particular differential chromatic refraction (DCR).