Bibcode
Gaia Collaboration; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; Mignard, F.; Drimmel, R.; Babusiaux, C.; Bailer-Jones, C. A. L.; Bastian, U.; Biermann, M.; Evans, D. W.; Eyer, L.; Jansen, F.; Jordi, C.; Katz, D.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri, X.; O'Mullane, W.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Valette, V.; van Leeuwen, F.; Walton, N. A.; Aerts, C.; Arenou, F.; Cropper, M.; Høg, E.; Lattanzi, M. G.; Grebel, E. K.; Holland, A. D.; Huc, C.; Passot, X.; Perryman, M.; Bramante, L.; Cacciari, C.; Castañeda, J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.; Hernández, J.; Jean-Antoine-Piccolo, A.; Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Ordóñez-Blanco, D.; Panuzzo, P.; Portell, J.; Richards, P. J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin, F.; Torra, J.; Els, S. G.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Lock, T.; Mercier, E.; Altmann, M.; Andrae, R.; Astraatmadja, T. L.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.; Cowell, S.; Creevey, O.; Cuypers, J.; Davidson, M.; De Ridder, J.; de Torres, A.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Frémat, Y.; García-Torres, M.; Gosset, E.; Halbwachs, J.-L.; Hambly, N. C.; Harrison, D. L.; Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle, H. E.; Hutton, A. et al.
Bibliographical reference
Astronomy and Astrophysics, Volume 595, id.A2, 23 pp.
Advertised on:
11
2016
Journal
Citations
1000
Refereed citations
958
Description
Context. At about 1000 days after the launch of Gaia we present the
first Gaia data release, Gaia DR1, consisting of astrometry and
photometry for over 1 billion sources brighter than magnitude 20.7. Aims: A summary of Gaia DR1 is presented along with illustrations of
the scientific quality of the data, followed by a discussion of the
limitations due to the preliminary nature of this release.
Methods: The raw data collected by Gaia during the first 14 months of
the mission have been processed by the Gaia Data Processing and Analysis
Consortium (DPAC) and turned into an astrometric and photometric
catalogue. Results: Gaia DR1 consists of three components: a
primary astrometric data set which contains the positions, parallaxes,
and mean proper motions for about 2 million of the brightest stars in
common with the Hipparcos and Tycho-2 catalogues - a realisation of the
Tycho-Gaia Astrometric Solution (TGAS) - and a secondary astrometric
data set containing the positions for an additional 1.1 billion sources.
The second component is the photometric data set, consisting of mean
G-band magnitudes for all sources. The G-band light curves and the
characteristics of 3000 Cepheid and RR Lyrae stars, observed at high
cadence around the south ecliptic pole, form the third component. For
the primary astrometric data set the typical uncertainty is about 0.3
mas for the positions and parallaxes, and about 1 mas yr-1
for the proper motions. A systematic component of 0.3 mas should be
added to the parallax uncertainties. For the subset of 94 000 Hipparcos
stars in the primary data set, the proper motions are much more precise
at about 0.06 mas yr-1. For the secondary astrometric data
set, the typical uncertainty of the positions is 10 mas. The median
uncertainties on the mean G-band magnitudes range from the mmag level to
0.03 mag over the magnitude range 5 to 20.7. Conclusions: Gaia
DR1 is an important milestone ahead of the next Gaia data release, which
will feature five-parameter astrometry for all sources. Extensive
validation shows that Gaia DR1 represents a major advance in the mapping
of the heavens and the availability of basic stellar data that underpin
observational astrophysics. Nevertheless, the very preliminary nature of
this first Gaia data release does lead to a number of important
limitations to the data quality which should be carefully considered
before drawing conclusions from the data.