Symposium S3  10-11 July 2023

Gaia: The (TWO) Billion Star Galaxy Census: The Magic of Gaia DR3


  • 20230127 Session Information updated.

Aims and scope

The updated ESA Gaia Billion Star Census of the Milky Way, was released in June 2022 as Gaia Data Release 3 (Gaia DR3). This release updated and extended Gaia EDR3, and contains the full five parameter astrometry for ~1.5 billion sources, along with low and medium resolution spectra and a wealth of associated data (such as mean radial velocities for brighter objects, see ( for details).

Gaia EDR3 and DR3 marked the most recent major milestone in the Gaia mission. Gaia continues to revolutionise our understanding of the formation history of the Milky Way, and is having a significant impact on many other areas of astronomy ranging from solar system science to quasars.

The key goals of this symposium will be for the Gaia/GREAT and related communities (and especially early stage researchers) to present and discuss their science highlights resulting from Gaia EDR3 and Gaia DR3. It will allow the Gaia project to update the science community with the latest scientific and technical performance of Gaia, review the most recent Gaia DR3 enabled science, and provide an early look ahead to the future release of Gaia DR4 (the full release of the 5 year Gaia nominal mission).

The symposium will also provide an opportunity to update the community as to the contents of the new Q3 2023 Gaia Focused Product Release (FPR). The symposium will include space for updates on initiatives aimed at optimising or leveraging the data from Gaia, together with presentations on the science topics where Gaia is having the highest impact. In addition the lunchtime session, will include demonstrations of the Gaia Data Archive, and plans for future enhancements. The lunch session will also include a set of poster lightening talks together with an update on next generation astrometry mission developments in the context of ESA?s Voyage 2050 programme.

GREAT plenary meetings have run since 2009, allowing members of the GREAT and the wider community to participate in a dynamic fashion. They are structured around Gaia updates, presentations from related organisations (e.g. ESO), reports from new initiatives, and new science results from the network activities.

This will be the 16th GREAT plenary (which since 2012 have been organised within the high impact EAS annual meetings - see the links to online materials at for the Gaia/ GREAT symposia held at the EAS meetings in Rome (S5), Turku (S11, SM5), Geneva (S3), La Laguna (S9), Athens (S1), Prague (S2), Liverpool (S2), Lyon (SS28), Leiden-virtual (S10), Leiden-virtual (S15)) and Valencia (S12 - talks online at

GREAT (an initiative of the ESA Gaia Project, Gaia Science Team and Data Processing and Analysis Consortium (DPAC) Executive) is a pan-European research network involving over 1000 researchers in 20+ countries with a common interest in maximising the science potential of Gaia ( GREAT, in the form of the MW-Gaia COST Action ( is currently financially supporting networking activities across Europe.


  • Gaia DR3: Highlight Science including a review of recent major science highlights in the Gaia DR3 release and an early look at the new Gaia Focused Product Release.
  • Gaia / GREAT/MW-Gaia / Gaia Unlimited Status
  • Gaia EDR3/DR3: Highlight Science (The Milky Way as a Galaxy)
  • Gaia EDR3/DR3: Highlight Science (The Birth, Life and Death of Stars)
  • Gaia EDR3/DR3: Highlight Science (from Solar system to reference frames)
  • Gaia networking and ground based synergies with Gaia
  • Lunch session with an update on the Gaia Archive, and update on the ESA Voyage 2050 L mission concept (GaiaNIR), and also an opportunity for poster presenters to deliver a 'lightening' talk of their (e-)poster.

Invited speakers

The speakers and programme will be available at the meeting website - see

  • Session 1 will include a headline talk from an invited speaker
  • Session 2 will include Gaia status update talks from Timo Prusti (Gaia), Anthony Brown and Antonella Vallenari (DPAC), Nic Walton (MW-Gaia)
  • All other session talks will be contributed presentations.

Scientific organisers

The co-Chairs are Nicholas Walton (Institute of Astronomy, University of Cambridge, UK), Anthony Brown (Leiden Observatory, Leiden University, NL), Timo Prusti (ESTEC, ESA) and Antonella Vallenari (INAF-Padua, IT).


Nicholas Walton (naw at

Updated on Sun Jan 29 13:08:53 CET 2023