Gaia's all-sky map of radial velocities
![](https://cdn.sci.esa.int/documents/33580/35361/1567214798365-ESA_Gaia_DR2_Average_Rad_Vel_625.jpg)
Date: 25 April 2018
Satellite: Gaia
Copyright: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO
All-sky view of radial velocities of stars in our Milky Way Galaxy, based on data from the second release of ESA's Gaia satellite. The radial velocity is the component of a star's true velocity through space measured along the line of sight.
The image shows the rotation pattern of stars in the Galaxy: stars shown in blue are moving towards the Sun, while stars shown in red are moving away. This information can be inferred from the red- or blue- shift of the light in the spectrum of a star as measured by Gaia's radial velocity spectrometer.
Acknowledgement: Gaia Data Processing and Analysis Consortium (DPAC); Gaia Coordination Unit 6; A. Brown, University of Leiden, The Netherlands; D. Katz, Observatory of Paris, France
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 IGO License.