provide (starting with Gaia Data Release 3) element abundances for stars brighter than G RVS ≈ 11 mag (reaching ~2 million stars in Gaia DR5).provide (starting with Gaia Data Release 3) astrophysical information, such as interstellar reddening, atmospheric parameters, and rotational velocities, for stars brighter than G RVS ≈ 12 mag (reaching ~5 million stars in Gaia DR5) and.Median radial velocities for some 7 million bright stars have been published in Gaia Data Release 2 while Gaia Data Release 3 contains median radial velocities for an extended sample of some 33 million stars with available atmospheric-parameter estimates provide radial velocities through Doppler-shift measurements using cross-correlation (reaching ~150 million stars in Gaia DR5).Spectroscopic observations are being collected with the spectroscopic instrument for all objects down to G RVS ≈ 16 mag, in order to:
#Gaia project tech track series#
In addition, Gaia Data Release 3 contains the Gaia Andromeda Photometric Survey (GAPS), consisting of the photometric time series for all sources (variable or not) located in a 5.5°-radius field centred on the Andromeda galaxy.
allow reconstruction of photometric time series for photometrically variable objects. Light curves (epoch photometry) and variable-star classifications of selected sources have been published as part of Gaia Data Release 2 while Gaia Data Release 3 contains the same information for a much extended sample.Astrophysical parameters for selected sources have been part of Gaia Data Release 2 and Gaia Data Release 3 contains object classifications and astrophysical parameters, together with the spectra they are based on, for a subset of spectroscopically and (spectro-)photometrically well-behaved objects provide astrophysical information for all objects, including astrophysical classification (for instance object type such as star, quasar, etc.) and astrophysical characterisation (for instance interstellar reddenings and effective temperatures for stars, photometric redshifts for quasars, etc.).enable chromatic corrections of the astrometric observations.Photometric observations are being collected with the photometric instrument, at the same angular resolution as the astrometric observations and for all objects observed astrometrically, in order to:
In crowded fields, only the brightest stars are observed such that the completeness limit becomes brighter than 20.7 th magnitude in such regions. The Gaia CCD detectors feature a pixel size of 10 μm (59 milli-arcsecond) in the scanning direction (also known as the along-scan direction) and the astrometric instrument has been designed to cope with object densities up to some 750,000 stars per square degree. (while solar-system objects have been published starting with Gaia Data Release 2, results for non-single stars, quasars, and extended objects have been published starting with Gaia Data Release 3). Gaia does not exclusively observe stars: all sufficiently point-like objects brighter than G ≈ 20.7 mag are observed, including solar-system objects such as asteroidsand Kuiper-belt objects, quasars, supernovae, multiple stars, etc. Each star transits the astrometric instrument on average ~12 times per year, leading to ~630/1260 CCD detector transits over the nominal/extended (five/ten-year) mission lifetime. Since mid-2014, Gaia has been performing micro-arcsecond (μas) global astrometry for nearly ~2,000 million stars down to G ≈ 20.7 mag by linking objects with both small and large angular separations in a network in which each object is connected to a large number of other objects in every direction. Expected Science Performance for the nominal and the extended mission based on GAIA (E)DR3Īstrometric Performance Photometric Performance Spectroscopic Performance PyGaia (Python toolkit)
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