Washington DC (SPX) Jan 14, 2022 Tom Jacobs of Bellevue, Washington, loves treasure hunts. Since...
Since 2010, the former U.S. naval officer has participated in online volunteer projects that allow anyone who is interested - "Citizen scientists" - to look through NASA telescope data for signs of exoplanets, planets beyond our solar system.
Now, Jacobs has helped discover a giant gaseous planet about 379 light-years from Earth, orbiting a star with the same mass as the Sun.
Uncovering this planet and pinning down its size and mass required a large collaboration between professional astronomers and citizen scientists like Jacobs.
How the discovery happened The signature for the newly discovered planet was hiding in data from NASA's Transiting Exoplanet Survey Satellite, or TESS. Using TESS data, scientists look for changes in brightness of nearby stars, which could indicate the presence of orbiting planets.
Jacobs is part of a group of citizen scientists who look at plots of TESS data, showing the change in a star's brightness over time, in search of new planets.
Many of them met while working on Planet Hunters, a NASA-funded citizen science project through Zooniverse that focused on data from NASA's Kepler spacecraft.
On February 1, 2020, Jacobs happened to notice a plot showing starlight from TOI-2180 dim by less than half a percent and then return to its previous brightness level over a 24-hour period, which may be explained by an orbiting planet that is said to "Transit" as it passes in front of the star from our point of view.
By measuring the amount of light that dims as the planet passes, scientists can estimate how big the planet is and, in combination with other measurements, its density.
A transit can only be seen if a star and its planet line up with telescopes looking for them.
Finding a second transit event was going to be difficult because there was so much uncertainty about when the planet would cross the face of its star again.