NASA's Kepler space telescope ran out of fuel in October last year. Data gathered during the course of its scientific mission, however, paved way to the discovery of a new exoplanet.
The newly identified planet dubbed K2-288Bb is twice the size of the Earth. It lies within its host star's habitable zone, which means the planet may have liquid water on its surface.
It could either be rocky like our home planet or gas-rich like Neptune.
The new world is located 226 light-years away in the constellation Taurus and lies in a stellar system called K2-288.
The stellar system has two dim, cool M-type stars about 5.1 billion miles apart, which is about six times the distance between Saturn and the sun.
The brighter of the pair is about half as large and massive as the sun while the dimmer one is about a third of the solar mass and size. K2-288Bb orbits this smaller and dimmer star every 31.3 days.
In 2017, Adina Feinstein, from the University of Chicago, and Makennah Bristow, from the University of North Carolina Asheville, who worked as interns with NASA astrophysicist Joshua Schlieder, were looking for evidence of transits, or the regular dimming of the star that occurs when an orbiting planet moves across its surface.
They were examining data from the fourth observing campaign of Kepler's K2 mission when they noticed two likely planetary transits in the system. The team, however, needed at least three transits to claim the discovery of a candidate planet and they did not find a third signal in the observations they reviewed.
It turned out that they did not analyze all of the data. Citizen scientists managed to find the third transit hiding in the first few days of data that had been forgotten.
"It's a very exciting discovery due to how it was found, its temperate orbit and because planets of this size seem to be relatively uncommon," said Feinstein, who presented the discovery at the 233rd meeting of the American Astronomical Society in Seattle on Monday, Jan. 7.
Exoplanet Explorers Program
K2-288 is now the third transiting planet system identified through the Exoplanet Explorers program, a project where ordinary citizens can search Kepler's K2 observations to find new transiting planets.
"Its discovery exemplifies the value of citizen science in the era of Kepler, K2, and the Transiting Exoplanet Survey Satellite," the researchers wrote in their study published in The Astronomical Journal on Jan. 7