Gaia in the UK

Taking the Galactic Census


On this page you can find the list of recent high priority Gaia Alerts for which we would like additional follow-up (usually photometry). There is a bias here towards objects which can be observed by the 0.4-2m class LCO telescopes available to schools via the Faulkes Telescope Project ( We will also add bright things which are suitable for observing with a small telescope. Teachers in British schools can register for their classes to observe on the Las Cumbres Observatory (LCO) network of robotic telescopes for free through the Faulkes Telescope Project - see Robotic Telescopes page for more information. Or, if you have access to a telescope, find out how to observe and submit your follow-up observations.

You can find a list of the Gaia Alerts which have been featured on this page on the Outreach Alerts archive page.

The complete list of all Gaia Science Photometric Alerts can be found at The alerts published during the validation phase (before July 2015) are also listed on the Gaia Photometric Science Alerts: Validation Phase page.

Explanation of Alerts table

Alert ID: The name that was assigned to this Alert. Click on the link to see more information about the Alert, including its Gaia spectra. For more information on interpreting spectra, see Gaia spectra.
Time: When Gaia first detected this Alert.
RA: The right ascension of the Alert (see Observing advice for more info).
Dec: The declination of the Alert.
Mag: The brightness of the Alert in Gaia magnitudes. For more information on magnitudes, see Observing advice. Note that a lower value for the magnitude means an Alert is brighter, and a higher value means it is fainter.
Classification: What sort of transient each Alert is.
Comment: Any additional information we have about why an alert is interesting, or information such as its distance.
Desired follow-up: Guidelines on what data we need from telescopes such as Faulkes for each Alert.
School: Initials of schools following-up this Alert (see Schools following-up Gaia Alerts).

Alert IDsort descending Time RA Dec Magnitude Classification Comment Outreach comment School
Gaia18aen 17 Jan 2018, 04:16 120.71694 -30.31032 11.33 unknown bright emission line star in Galactic plane brightens by 1 magnitude

This is bright and in reach of modest telescopes - BUT only really observable from the Southern Hemisphere. We've no idea what this is - please monitor

Gaia18aod 8 Mar 2018, 09:11 208.36495 -67.41694 6.77 Nova confirmed Galactic Nova, extremely bright, aka Nova Circini 2018 (PNV J13532700-6725110)

An opportunity to observe a really bright Galactic Nova.

Gaia18asi 24 Mar 2018, 01:36 275.09139 7.18534 12.00 XRB bright outburst in Gaia source, aka ASASSN-18ey, aka MAXI J1820+070, candidate X-ray binary

This was discovered first in the optical (by ASAS-SN) then in X-rays, and then we saw it brighten in Gaia. It's very likely to be an X-ray binary with a black hole at the centre. Continued photometric monitoring of this new system is encouraged - especially in a blue filter