Gaia in the UK

Taking the Galactic Census


Gaia data releases

The Gaia data accumulation is split into segments of roughly one year in length. The processing of the data is taking place in cycles, where each cycle covers all completed data segments up to an agreed date. The Gaia data is self-calibrating, in other words, it defines its own "system". Such systems are created for the astrometric as well as the photometric data. In each cycle the system is re-defined, getting rapidly closer to the final fully converged system. The next steps then involve connecting these internal Gaia systems to ground-based systems. For the astrometric data this amounts to establishing the celestial reference system, in the photometric data this involves the detailed calibration of the Gaia pass bands. The great advantage of this approach is that a system is obtained with well-defined internal accuracy, and a clear transformation is established to define the external (or absolute) accuracies.

Gaia DR5

Pending further approvals of mission extensions additional release(s) will take place (currently extension until the end of 2022 has been approved and an indicative approval until the end of 2025 has been given). Currently Gaia DR5 is anticipated, containing all collected data.

Gaia DR4

Based on 66 months of data. To be published not before the end of 2025.

The catalogue will be consisting of:

  • Full astrometric, photometric, and radial-velocity catalogues.
  • All available variable-star and non-single-star solutions.
  • Source classifications (probabilities) plus multiple astrophysical parameters (derived from BP/RP, RVS, and astrometry) for stars, unresolved binaries, galaxies, and quasars. Some parameters may not be available for faint(er) stars.
  • An exo-planet list.
  • All epoch and transit data for all sources.

Gaia FPR (Focused Product Release)

Released on 10 October 2023.

The release consists of:

  • Updated astrometry for Solar System objects.
  • Astrometry and photometry from engineering images taken in selected regions of high source density (only Omega Cen for this FPR).
  • The first results of quasars' environment analysis for gravitational lenses search.
  • Extended radial velocity epoch data for Long Period Variables.
  • Diffuse Interstellar Bands from aggregated RVS spectra.
  • Pre-main sequence accretion parameters (no longer part of FPR; postponed to DR4).

See Gaia Focused Product Release page for information about Gaia Focused Product Release.

Gaia Data Release 3

Gaia Data Release 3 delays. Gaia Early Data Release 3 and Gaia Data Release 3 have been affected by the COVID-19 pandemic, and have been be delayed. Release shedule updates have been published at

Gaia DR3 is based on 34 months of mission data resulting in better accuracy with respect to Gaia DR2. Gaia DR3 is split into two releases:

  • The early release, Gaia EDR3, published on 3 December 2020. Gaia EDR3 will contain astrometry and (integrated) photometry i.e. positions, parallaxes, proper motions, G-band fluxes as well as integrated red- (RP) and blue-band (BP) fluxes. First results for a predefined list of quasars and extended objects may also be included
  • Gaia DR3, published on 13 June 2022. Gaia DR3 which supersedes Gaia EDR3. The source list and any data published in Gaia EDR3 do not change, but have been copied into Gaia DR3. The additional products include:
    • radial velocities (significantly more due to fainter magnitude limit),
    • BP/RP/RVS spectra,
    • Solar system data (significantly more sources included),
    • variability information (significantly more objects due to longer time interval),
    • results for non-single stars, and
    • astrophysical parameters based on spectra.

See Gaia Data Release 3 announcement and Gaia Data Release 3 page for information about Gaia Data Release 3.

See the Gaia Early Data Release 3 page for information about Gaia Early Data Release 3.

Gaia Data Release 2

Release date: 25 April 2018.

Gaia DR2 data is based on data collected between 25 July 2014 (10:30 UTC) and 23 May 2016 (11:35 UTC), spanning a period of 22 months of data collection (or 668 days), as compared to Gaia DR1 which was based on observations collected in the first 14 months of Gaia's routine operational phase.
The reference epoch for Gaia DR2 is J2015.5 (with respect to the J2015.0 epoch for Gaia DR1). Positions and proper motions are referred to the ICRS, to which the optical reference frame defined by Gaia DR2 is aligned. The time coordinate for Gaia DR2 results is the barycentric coordinate time (TCB).

See Gaia Data Release 2 for more information.

Gaia DR2 data

The Gaia DR2 data can be accessed at:

Gaia Data Release 1

Release date: 14 September 2016.

Gaia DR1 catalogue contains astrometric and photometric data for over 1 billion sources brighter than magnitude 20.7 in Gaia's photometric G-band (white light - from about 350 to 1000 nanometres). Gaia DR1 is based on observations collected between 25 July 2014 and 16 September 2015. See Gaia Data Release 1 for more information.
Gaia Data Release 1 data

Gaia DR1 data is available from the ESA Gaia Archive and from the main partner data centres:

    Centre de Données astronomiques de Strasbourg (CDS)
    ASI Science Data Center (ASDC)
    Astronomisches Rechen-Institut (ARI)
    Leibniz-Institut für Astrophysik Potsdam (AIP).

Direct data downloads

Gaia data can also be downloaded directly in CSV format from .

Gaia data release schedule

Visit Gaia Data Release Scenario for more information about Gaia data release schedule.

Gaia auxiliary data

Auxiliary data provided to support the use of Gaia data (including Gaia photometric passbands, scanning law and cosmic ray detections) is available from Auxiliary Data page on ESA's website.

Gaia Photometric Science Alerts

The Gaia Science Alerts (GSA) project is searching for transient events (a transient is anything in the sky which appears, disappears or changes) in the data from Gaia, and publishes transient alerts to the world in real time on the Gaia Photometric Science Alerts website.

Extensive background information about each transient is also available from GSA website. This information includes light curves and light curve data for all transients, and spectra obtained with Gaia's blue and red photometers (BP/RP spectra) are available for most of the alerts. The spectra are uncalibrated – see Gaia spectra for information on how to interpret these spectra and some examples.

More information about the Gaia Photometric Science Alerts project, including observing advice, can be found in Alerts section of this website.

Solar System Objects

Gaia Follow-Up Network for Solar System Objects (Gaia-FUN-SSO)

The Gaia Follow-Up Network for Solar System Objects (Gaia-FUN-SSO) has been set up to coordinate ground-based observations on alert triggered by the data processing system during the mission for the confirmation of newly detected moving objects or for the improvement of orbits of some critical targets. Gaia scans the sky following a predefined scanning law and such ground-based observations are required to avoid the loss of newly detected Solar System objects and to facilitate their subsequent identification by the satellite.

The alerts, including the ephemeris to help finding the targets, are published on Gaia-FUN-SSO  website, where they can be accessed by the registered members of the Gaia Follow-up network. The network currently consists in about 80 observers in 27 observing sites, spread all over the world (November 2016).

Gaia Groundbased Observational Service for Asteroids (Gaia-GOSA)

The Gaia Groundbased Observational Service for Asteroids (Gaia-GOSA) is a web service to coordinate observers with small to medium size telescopes (so mainly amateur astronomers) with the goal of gathering photometric light curves of a selection of asteroids.
As an observer you can register for free at the Gaia-GOSA website. After providing instrument setup and location, the website will compute what asteroids are visible to the entered observer for a given date, and results will be displayed while giving priority to two kinds of targets:

  • Hot targets: these are targets that are scientifically interesting targets being observed by Gaia within the next 24 hours.
  • Follow-up targets: asteroids with existing observations but with missing segments of the lightcurves, and thus with a need for follow-up observations.

After a successful observation, users can submit their raw frames, which are then processed and analysed by the Gaia-GOSA team. First observations of the Gaia-GOSA service were obtained in 2016. So far (as of November 2017) more than 300 light curves have been gathered by Gaia-GOSA users and data are now being processed. The data gathered through this service will be used to validate Gaia measurements of asteroids but will also enhance their scientific exploitation.
The service was developed by Adam Mickiewicz at the University of Poznań and a Polish IT company iTTi, with collaboration of Gaia DPAC members at the Observatoire de la Côte d'Azur and from the University of Barcelona, under the ESA Contract "Gaia-GOSA: An interactive service for asteroid follow-up observations". Read more about Gaia-GOSA.

Gaia Object Generator and Gaia Universe Model Snapshot

Gaia Object Generator (GOG) the Gaia Universe Model Snapshot (GUMS) 18 have been made available in HDF5 format and TAP access at GUMS and GOG 20 are included in the bulk download available from Gaia Archive.


Page last updated: 26 March 2024