What stars are made of can tell us about their birthplace and their journey afterwards, and therefore about the history of the Milky Way. With today’s data release, Gaia is bringing us a chemical map of the galaxy.

Some stars contain more ‘heavy metals’ than others. During the Big Bang, only light elements were formed (hydrogen and helium). All other heavier elements – metals – are built inside stars. When stars die, they release these metals into the gas and dust between the stars called the interstellar medium, out of which new stars form. Active star formation and death will lead to an environment that is richer in metals. Therefore, a star’s chemical composition is a bit like its DNA, giving us crucial information about its origin.

With Gaia, we see that some stars in our galaxy are made of primordial material, while others like our Sun are made of matter enriched by previous generations of stars. Stars closer to the centre and plane of our galaxy are richer in metals than stars at larger distances.

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Acknowledgements:

Based on the paper by the Gaia Collaboration 

      "Gaia Data Release 3: Chemical cartography of the Milky Way"

Gaia Data Release 3 is published on

      June 13, 2022

Main Video/Data sets: ESA/Gaia/DPAC, 

     Stefan Jordan, Toni Sagristà, 

     Alejandra Recio-Blanco, Pedro Alonso Palicio, 

     Patrick de Laverny, Paul McMillan.

Narrator: Paul McMillan

Video of focal plane: ESA

RVS Spectrum animation:  ESA/Gaia/DPAC/CU8-CU6, Alejandra Recio-Blanco and the GSPspec team. 

We wish to thank the Gaia Data Processing Centre at the Centre National  d'Etudes Spatiales (CNES; DPCC) for producing the high-quality  spectroscopy and data analysis upon which this work rests.

Music: "Canon" by Johann Pachelbel 

      Interpreted by: Jean-Baptiste Bourrel & Alejandra Recio-Blanco 

      Music recorded and mixed by Didier Farrugia 

     Music's artistic advisor: Claude Galvez

The main videos were created with Gaia Sky, developed by Toni Sagristà

Gaia Sky can be downloaded from 

www.zah.uni-heidelberg.de/gaia/outreach/gaiasky”