Much of the work done in astronomy requires large groups of people co-operating and working together to make new discoveries. While most of that work is done by professional astronomers, there are some occasions where members of the public help as well. Recently, citizen scientists have helped comb through data from a NASA telescope to identify a gas giant planet located 379 light-years away.
The team of citizen scientists used data from the Transiting Exoplanet Survey Satellite, or TESS, to identity planet TOI-2180 b. It orbits a star with a similar mass to our sun, and a year there lasts 261 days, which makes it one of the further-out gas giants discovered outside the solar system. “Discovering and publishing TOI-2180 b was a great group effort demonstrating that professional astronomers and seasoned citizen scientists can successfully work together,” said Tom Jacobs, one of the citizen scientists who volunteered for the project, in a statement. “It is synergy at its best.”
Many exoplanets are spotted by looking for transits, or times when a planet passes between a star and Earth. The dip in the brightness of the star can tell astronomers about the properties of the planet. However, this requires the telescope, the planet, and the star to be carefully lined up. It also works best with planets that are close to their stars.
“With this new discovery, we are also pushing the limits of the kinds of planets we can extract from TESS observations,” said researcher Diana Dragomir. “TESS was not specifically designed to find such long-orbit exoplanets, but our team, with the help of citizen scientists, are digging out these rare gems nonetheless.”
Transits are usually spotted by computer algorithms, but in this case, because it orbits far from its star, the planet only made one transit in the data. That’s where the citizen scientists came in — they helped to identify potential exoplanets based on their light curves, or graphs of brightness from a star over time.
“The manual effort that they put in is really important and really impressive because it’s actually hard to write code that can go through a million light curves and identify single transit events reliably,” said fellow researcher Paul Dalba. “This is one area where humans are still beating code.”
Now both the professionals and the citizen scientists are keen to see what they find when TESS observes the same star again in February when they are hoping to find confirmation of the planet’s orbit.
“We love contributing to science,” Jacobs said. “And I love this type of surveying, knowing that one is in new undiscovered territory not seen by any humans before.”
The research is published in The Astronomical Journal.
