Citizen science project makes 20 new astronomical discoveries

The public has played an instrumental role in identifying cosmic explosions for a citizen science project involving the University of Leicester.

Twenty astronomical discoveries have been made through the ‘Kilonova Seekers’ project which aims to find kilonovae – the cosmic explosions of neutron stars and black holes colliding in distant galaxies. 

The project has seen more than 2,000 volunteers from 105 countries work on 600,000 classifications over a six-month period.

Volunteers are asked spot differences in data from a pair of Gravitational-wave Optical Transient Observer (GOTO) telescopes, located on opposite sides of the planet – on La Palma, Canary Islands, and Siding Spring Observatory, Australia.

Dr Rhaana Starling, who co-leads a science working group for GOTO at the University of Leicester, said: “I got involved in GOTO in its infancy, seeing the huge potential for discovery of short-lived, catastrophic events like the deaths of massive stars and merger of compact stars, which lead to the formation of new black holes.

“GOTO can repeatedly survey vast areas of the sky in a very short time, which enables unique discoveries, but also generates vast amounts of data that we need to search. The global network of dedicated citizen scientists that our Kilonova Seekers Zooniverse project has amassed, means we can make full use of these data and the discoveries so far have been very exciting.”

Five of the 20 citizen scientist discoveries have been identified as Type la Supernovae, which are powerful and bright explosions of stars.

Type la Supernovae are important in astronomy because they have a consistent peak brightness, which makes them useful as ‘standardisable candles’ to measure distances in space. By knowing how bright these supernovae should be, astronomers can calculate how far away they are, which helps measure the accelerating expansion of the universe.

The other discovery that has been classified is a cataclysmic variable star. This is a binary star system consisting of a white dwarf star stealing matter from its companion star, which causes bright flashes of light.

One of the key accomplishments of the project is the speed of classification and consensus from the volunteers.

Scientists monitor alerts from gravitational wave detectors LIGO, Virgo and KAGRA, which trigger GOTO telescopes within 30 seconds to begin searching the sky. Any images taken are then shared with the public via the Zooniverse, the world’s largest and most popular platform for facilitating citizen science.

Kilonova Seekers launched publicly on Zooniverse on 11 July 2023 and there were 1,000 classifications within the first 30 minutes.

Based on data obtained from Google Analytics, there are participants from every continent, except Antarctica. The wide accessibility of Zooniverse projects enables researchers to reach countries that may be traditionally underrepresented in astronomical communities.

The United Kingdom is the second largest contributor, with 615 volunteers on the Kilonova Seekers project, behind the United States which has a total of 1,284 volunteers. Volunteers from Portugal are the most active, with each person viewing over 2,750 pages on average.

The first stage of Kilonova Seekers is presented in a paper published in Monthly Notices of the Royal Astronomical Society. 

GOTO is run by an international collaboration of researchers, of which the University of Leicester is a core member. Alongside Dr Starling the GOTO team at the University comprises Professor Paul O’Brien, Dr Rob Eyles-Ferris and PhD students Miti Patel and Yashaswi Julakanti.