Estimated distances to 1.33 billion stars in Gaia DR2
Short Name:
gdr2dist scs
Date:
27 Dec 2024 08:31:05
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.
HSOY is a catalog of 583'001'653 objects with precise astrometry based on
PPMXL and Gaia DR1. Typical formal errors at mean epoch in proper motion are
below 1 mas/yr for objects brighter than 10 mag, and about 5 mas/yr at the
faint end (about 20 mag). South of -30 degrees, astrometry is significantly
worse. HSOY also contains, where available, USNO-B, Gaia, and 2MASS
photometry. HSOY's positions and proper motions are given for epoch J2000.
The catalog becomes severely incomplete faintwards of 16 mag in the G-band.
The mean epochs are typically very close to Gaia's J2015.
HSOY still contains about 0.7% spurious close
"binaries" (non-matched stars) from the original USNO-B (marked with non-NULL
clone). Also, failed matches within Gaia DR1 contribute another 1.5% spurious
pairs (marked with non-NULL comp). In both cases, astrometry presumably is
sub-standard.
More information is available at http://dc.g-vo.org/hsoy.