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I/345 Gaia DR2 (Gaia Collaboration, 2018)
The following files can be converted to FITS (extension .fit or fit.gz)
gaia2.sam rvstdcat.dat rvstdmes.dat allwise.dat iers.dat cepheid.dat
rrlyrae.dat lpv.dat varres.dat shortts.dat tsstat.dat numtrans.dat
transits.dat scalar.dat segments.dat outliers.dat ssoobj.dat
ssoorb.dat ssores.dat ssoobs.dat
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Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/345
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up]
drwxr-xr-x 6 cats archive 4096 Feb 7 18:29 [TAR file]
-rw-r--r-- 1 cats archive 682 Dec 19 14:34 .message
-r--r--r-- 1 cats archive 125530 Dec 14 2020 ReadMe
-rw-r--r-- 1 cats archive 1005 Dec 19 14:34 +footg5.gif
-rw-r--r-- 1 cats archive 6917 Dec 19 14:45 +footg5.png
-rw-r--r-- 1 cats archive 2978 Dec 19 14:34 +footg8.gif
-rw-r--r-- 1 cats archive 36494 Dec 19 14:45 +footg8.png
-r--r--r-- 1 cats archive 10576916 Apr 12 2018 allwise.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 1279869 Nov 8 2019 cepheid.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 182 Sep 21 2018 custom.htx
-r--r--r-- 1 cats archive 279586 Apr 13 2018 gaia2.sam.gz [Uncompressed]
-r--r--r-- 1 cats archive 81780 Apr 12 2018 iers.dat [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 3818200 Nov 8 2019 lpv.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 5858589 Apr 16 2018 numtrans.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 7155892 Apr 17 2018 rm.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 8732303 Apr 16 2018 rmout.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 53982995 Apr 17 2018 rmseg.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 16896985 Nov 8 2019 rrlyrae.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 402875 Apr 18 2018 rvstdcat.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats www-data 399329 Apr 18 2018 rvstdcat.ori.gz [Uncompressed]
-r--r--r-- 1 cats www-data 964835 Apr 12 2018 rvstdmes.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 90241 Apr 12 2018 shortts.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 185172 Apr 12 2018 ssoobj.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 209897676 Apr 13 2018 ssoobs.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 786442 Apr 12 2018 ssoorb.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 97668077 Apr 12 2018 ssores.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 40320 Aug 22 2022 tab_1345_1_I_345_gaia2.moc.fits
-r--r--r-- 1 cats archive 2107353705 May 15 2018 transits.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-r--r--r-- 1 cats archive 98302791 Apr 13 2018 tsstat.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
-rw-r--r-- 1 cats archive 10225424 Nov 8 2019 varres.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe :I/345 Gaia DR2 (Gaia Collaboration, 2018)
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Gaia data release 2 (Gaia DR2).
Gaia collaboration
<Astron. Astrophys., 616, A1 (2018)>
=2018A&A...616A...1G
=2018yCat.1345....0G
=doi:10.5270/esa-ycsawu7
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ADC_Keywords: Surveys ; Stars, standard ; Positional data ; Proper motions ;
Photometry, photographic ; Cross identifications ;
Radial velocities ; Stars, variable ; Minor planets;
Parallaxes, trigonometric
Mission_Name: Gaia
Keywords: catalogs - astrometry - techniques: radial velocities -
stars: fundamental parameters - stars: variables: general -
minor planets, asteroids: general
Abstract:
Gaia Data Release 2. Summary of the contents and survey properties:
We present the second Gaia data release, Gaia DR2, consisting of
astrometry, photometry, radial velocities, and information on as-
trophysical parameters and variability, for sources brighter than
magnitude 21. In addition epoch astrometry and photometry are provided
for a modest sample of minor planets in the solar system.
A summary of the contents of Gaia DR2 is presented, accompanied by a
discussion on the differences with respect to Gaia DR1 and an overview
of the main limitations which are still present in the survey.
Recommendations are made on the responsible use of Gaia DR2 results.
Methods. The raw data collected with the Gaia instruments during the
first 22 months of the mission have been processed by the Gaia Data
Processing and Analysis Consortium (DPAC) and turned into this second
data release, which represents a major advance with respect to Gaia
DR1 in terms of completeness, performance, and richness of the data
products.
Gaia DR2 contains celestial positions and the apparent brightness in G
for approximately 1.7 billion sources. For 1.3 billion of those
sources, parallaxes and proper motions are in addition available. The
sample of sources for which variability information is provided is
expanded to 0.5 million stars. This data release contains four new
elements: broad-band colour information in the form of the apparent
brightness in the G_BP_ (330-680nm) and G_RP_ (630-1050nm) bands is
available for 1.4 billion sources; median radial velocities for some
7 million sources are presented; for between 77 and 161 million
sources estimates are provided of the stellar effective temperature,
extinction, reddening, and radius and luminosity; and for a
pre-selected list of 14000 minor planets in the solar system epoch
astrometry and photometry are presented. Finally, Gaia DR2 also
represents a new materialisation of the celestial reference frame in
the optical, the Gaia-CRF2, which is the first optical reference frame
based solely on extragalactic sources. There are notable changes in
the photometric system and the catalogue source list with respect to
Gaia DR1, and we stress the need to consider the two data releases as
independent.
Gaia DR2 represents a major achievement for the Gaia mission,
delivering on the long standing promise to provide parallaxes and
proper motions for over 1 billion stars, and representing a first step
in the availability of complementary radial velocity and source
astrophysical information for a sample of stars in the Gaia survey
which covers a very substantial fraction of the volume of our galaxy.
The catalogue of radial velocity standard stars
(Soubiran et al., 2018A&A...616A...7S)
The Radial Velocity Spectrometer (RVS) on board of Gaia having no
calibration device, the zero point of radial velocities needs to be
calibrated with stars proved to be stable at the level of 300m/s
during the Gaia observations. A dataset of about 71000 ground-based
radial velocity measurements from five high resolution spectrographs
has been compiled. A catalogue of 4813 stars was built by combining
these individual measurements. The zero point has been established
using asteroids. The resulting catalogue has 7 observations per star
on average on a typical time baseline of 6 years, with a median
standard deviation of 15m/s. A subset of the most stable stars
fulfilling the RVS requirements has been used to establish the zero
point of the radial velocities provided in Gaia DR2. The stars not
used for calibration are used for the RVS data validation.
Description:
Contents of Gaia DR2:
The five-parameter astrometric solution - positions on the sky
(alpha,delta), parallaxes, and proper motions - for more than 1.3
billion (10^9^) sources, with a limiting magnitude of G=21 and a
bright limit of G =3. Parallax uncertainties are in the range of up
to 0.04 milliarcsecond for sources at G<15, around 0.1mas for
sources with G=17 and at the faint end, the uncertainty is of the
order of 0.7mas at G=20. The corresponding uncertainties in the
respective proper motion components are up to 0.06mas/yr (for
G<15mag), 0.2mas/yr (for G=17mag) and 1.2mas/yr (for G=20mag). The
Gaia DR2 parallaxes and proper motions are based only on Gaia data;
they do no longer depend on the Tycho-2 Catalogue.
Median radial velocities (i.e. the median value over the epochs) for
more than 6 million stars with a mean G magnitude between about 4 and
13 and an effective temperature (Teff) in the range of about 3550 to
6900K. This leads to a full six-parameter solution: positions and
motions on the sky with parallaxes and radial velocities, all combined
with mean G magnitudes. The overall precision of the radial velocities
at the bright end is in the order of 200-300m/s while at the faint
end the overall precision is approximately 1.2km/s for a Teff of
4750K and about 2.5km/s for a Teff of 6500K.
An additional set of more than 200 million sources for which a
two-parameter solution is available: the positions on the sky
(alpha,delta) combined with the mean G magnitude. These sources will
have a positional uncertainty at G=20 of about 2mas, at J2015.5.
G magnitudes for more than 1.5 billion sources, with precisions
varying from around 1 milli-mag at the bright (G<13) end to around 20
milli-mag at G=20. Please be aware that the photometric system for the
G band in Gaia DR2 will be different from the photometric system as
used in Gaia DR1.
G_BP_ and G_RP_ magnitudes for more than 1.1 billion sources, with
precisions varying from a few milli-mag at the bright (G<13) end to
around 200 milli-mag at G=20. Full passband definitions for G, BP and
RP. These passbands are now available for download. A detailed
description is given here. Epoch astrometry for more than 13,000 known
asteroids based on more than 1.5 million CCD observations. 96% of the
along-scan (AL) residuals are in the range -5 to 5mas, and 52% of the
AL residuals are in the range of -1 to 1mas. The observations will be
published in Gaia DR2 and also delivered to the Minor Planet Center
(MPC).
Subject to limitations the effective temperatures Teff for more than
150 million sources brighter than 17th magnitude with effective
temperatures in the range 3000 to 10,000 K. For a subset of these
sources also the line-of-sight extinction AG and reddening E(BP-RP)
will be given, as well as the luminosity and radius.
Lightcurves for more than 500,000 variable sources consisting of
Cepheids, RR Lyrae, Mira and Semi-Regular Candidates as well as
High-Amplitude Delta Scuti, BY Draconis candidates, SX Phoenicis
Candidates and short time scale phenomena.
Planned cross-matches between Gaia DR2 sources on the one hand and
Hipparcos-2, Tycho-2, 2MASS PSC, SDSS DR9, Pan-STARRS1, GSC2.3,
PPM-XL, AllWISE, and URAT-1 data on the other hand.
Catalogue of radial velocity standard stars
(Soubiran et al., 2018A&A...616A...7S):
Individual and combined radial velocity measurements are presented for
4813 stars in rvstdcat.dat and rvstdmes.dat files.