NASA has announced that the data from the Transiting Exoplanet Survey Satellite (TESS) has evidence of a new planet and the person responsible for this new discovery is a 17-year-old NASA intern Wolf Cukier.
The newly found planet is 1,300 light-years away from Earth and what makes this discovery even more amusing is the fact that it is the first-ever circumbinary planet captured by TESS. Scientists have named the planet as TOI 1338 b, where TOI stands for TESS Object of Interest.
How did NASA intern found the planet
With its four cameras, TESS captures an image of a patch of sky every 30 minutes, enabling scientists to make graphs of changes in the brightness of stars. A decrease in the brightness of a single star indicates that a planet has crossed in front of it. The images captured by TESS are uploaded to Hunters TESS citizen science project and NASA invites volunteers to watch the online transmission for patterns in star brightness.
During the first week of the internship in the summer of 2019, Cukier was tasked with examining the TESS data flagged by citizen-scientists for variations in star brightness when he came across a system that included two orbiting stars. He managed to identify a body in that system, which was later verified as a planet “TOI 1338 b”.
“I was looking through the data for everything the volunteers had flagged as an eclipsing binary, a system where two stars circle around each other and from our view eclipse each other every orbit,” Cukier said. “About three days into my internship, I saw a signal from a system called TOI 1338. At first, I thought it was a stellar eclipse, but the timing was wrong. It turned out to be a planet.”
The first circumbinary planet discovered by TESS
The circumbinary planets are more difficult to detect than your planet that orbits only one star. Observations of binary systems are biased toward finding larger planets because the transits of smaller bodies don’t have as big an effect on the stars’ brightness, lead author and research scientist at the SETI Institute and Goddard, Veselin Kostov said.
This is why Cukier had to visually examine each potential transit to search for the planet. Initially, he also thought that TOI 1338 b’s transit was a result of the smaller star in the system passing in front of the larger one, but the timing was wrong for an eclipse. He then identified it as a planet and consulted on his find with his mentor. Using the archival data from earlier surveys of the system, a verification process began which confirmed the existence of a planet, later came to be known as TOI 1338 b.
“These are the types of signals that algorithms really struggle with,” Kostov said. “The human eye is extremely good at finding patterns in data, especially non-periodic patterns like those we see in transits from these systems.”
Circumbinary planets or the planets orbiting two stars are not rare but the TOI 1338 b is the first such planet discovered using TESS data. NASA’s Kepler and K2 missions previously discovered 12 circumbinary planets in 10 systems– all similar to TOI 1338 b.
The TOI 1338 system
According to NASA, the newly discovered planet is about 6.9 times as large as Earth– between the sizes of Neptune and Saturn. Due to its positioning around the two stars it orbits, TOI 1338 b experiences regular solar eclipses and the space agency estimates that the orbit of the planet is stable for at least the next 10 million years.
The planet orbits in almost exactly the same plane as the stars, so it experiences regular stellar eclipses, NASA said in a press release. The two stars orbit each other every 15 days and the whole TOI 1338 system lies 1,300 light-years away in the constellation Pictor. As per the space agency, one of the stars in the TOI 1338 system is about 10 per cent more massive than our Sun, while the other is cooler, dimmer and only one-third the Sun’s mass.