Gaia mission status

 

The Gaia mission was launched on 19 December 2013 and after a period of commissioning, started its science operations phase on 25 July 2014. It has scanned the sky for more than 10 years, and stopped taking new science observations on 15 January 2025.

The data gathered over the course of these years is processed by the Gaia Data Processing and Analysis Consortium, and published in the form of Gaia data releases.

Gaia science observation phase
Average distance of Gaia space telescope from Earth (in km) 1,510,000
Number of days in science operations (25 July 2014 - 15 January 2025) 3827
Operational data collected
Volume of science data collected (in GB) 141,038
Number of object transits through the focal plane 267,336,261,480
Number of astrometric CCD measurements 2,635,171,720,297
Number of photometric CCD measurements 530,821,357,368
Number of object transits through the RVS instrument 17,471,272,143
Number of spectroscopic CCD measurements 52,062,041,736
Total number of CCD measurements (astrometric + photometric + spectroscopic) 3,218,055,119,401
Statistics  
Average number of objects scanned per second 809
Average number of CCD measurements per second 9,732
Nitrogen gas consumed (in kg) 55
Camera pixels onboard 937,782,000
Commands sent to the spacecraft 2,800,000
Ground station time used (hours) 50,000
Spacecraft pirouettes (full scan circles) 15,300
 

 

The table above presents the mission status as obtained for its full science observation phase. It is based on the predicted spacecraft ephemeris and data accumulated by the science Data Integrity and Accountability Checks (DIAC) service.

These numbers should be interpreted with some care:

  • Object transits refer to on-board detections. An object can be a genuine star (most of the time), but also an asteroid, a QSO, an unresolved external galaxy, a cosmic ray, a false detection, etc. Actually, an object refers to an allocated window which, in dense areas, can contain multiple astronomical (light) sources.
  • The numbers do not include virtual objects (VOs).
  • Astrometric measurements refer to the 62 astrometric CCDs and the 14 Sky-Mapper CCDs.
  • Photometric measurements refer to the 14 blue- and red-photometer CCDs.
  • Spectroscopic measurements refer to the 12 radial-velocity-spectrograph (RVS) CCDs.
  • The number of spectroscopic transits does not necessarily equal three times the number of object transits through the RVS instrument. For instance, not all focal-plane transits lead to three CCD transits (stars can move out of the CCD in the across-scan direction).