Massive Jupiter-sized exoplanet orbits two stars and faces three eclipses: Experts

An international science team led by Veselin B. Kostov, of NASA’s Goddard Space Flight Center, has made a stunning discovery about an exoplanet. Interestingly, this gaseous planet named TIC 172900988 b is a circumbinary planet, meaning it orbits two stars and is as big as our solar system’s Jupiter. What's more intriguing is the fact that it completes one revolution around the stars in about 200 days and as a result, undergoes three eclipses.

A planet that orbits two stars, which in turn orbit each other

Astronomers were able to trace the existence of this planet using the data presented by the Transiting Exoplanet Survey Satellite or TESS. This telescope has discovered more than 150 confirmed exoplanets since its launch in 2018, including the new giant, and nearly 3,500 exoplanet candidates are awaiting further confirmation, as per NASA. This gaseous giant was discovered by observing the phenomenon called Planetary transits - the phenomenon of a planet crossing its star's face. The TESS scanned thousands of stars at a time, hunting for the tiny dip in starlight when an orbiting planet crosses the face of its parent star. 

Astronomers reported that this planet is a circumbinary as it orbits two stars, which in turn orbit each other. "But even among circumbinaries, this discovery stands out. Its year, once around the two stars, takes about 200 ­days. That would normally present a big challenge to astronomers trying to figure out the dynamics of this system", said an official statement by NASA's Exoplanet Exploration Program. It revealed that rather than waiting for 200 days to confirm two planetary transits, the scientists only had 30 days to observe the circumbinary planetary system before TESS moved on to another patch of sky. As per the statement, astronomers were able to observe three eclipses in just 20 days owing to the configuration of these stars and their planet.

Thanks to the configuration of these stars and their planet, and the advantages of our angle of view from Earth, astronomers had most of the information they needed. The three eclipses could be observed as part of the 20-day orbit of the stars around each other; and the scientists saw only a five-day gap between the planet’s transit of the first star and the second one.

Surprisingly, high-resolution imaging in near-infrared light hinted that there also might be a third star encircling both stars and the newly discovered planet in a massive orbit that takes about 5,000 years for one revolution. Astronomers said that this star has a 10% lower mass than the other two stars and is only 30 times more massive than the giant planet.

Image: NASA