NASA discovers huge exoplanet with a tail

The hot Jupiter WASP-69b is trailing a vast tail that’s at least 7 times the width of the planet, scientists say.

A comet-like planet beyond our solar system is losing a lot more atmosphere in its vast tail than previously thought, intriguing astronomers and sparking new questions about how planets evolve with their parent stars, reported Space.com.

The exoplanet WASP-69b, a hot, puffy gas giant 160 light-years from Earth that circles its host star in a speedy 3.9 days, first rose to fame in 2018 when astronomers found a possible comet-like tail of gas leaking from the planet’s atmosphere. That tail, which was thought to be just a tiny trail of helium particles, if it existed at all, is now estimated to be at least 350,000 miles long (563,270 kilometers), about seven times the width of the planet, as its atmosphere is blown away by a steady barrage of solar wind from its star.

“It’s getting bathed in radiation,” study co-author Dakotah Tyler of the University of California Los Angeles (UCLA), said during a press briefing last January at the 243rd meeting of the American Astronomical Society in New Orleans. “If you’re ever considering retiring, I would suggest that you do not consider retiring on this planet,” he added, reported Space.com. 

The WASP-69b system is a gem because we have a rare opportunity to study atmospheric mass-loss in real time”, said Erik Petigura, astronomer at UCLA.

Tyler shared new data of WASP-69 b’s leaking atmosphere from the Keck Observatory in Hawaii, also described in a paper published in The Astrophysical Journal. The latest observations reveal the atmosphere is breaking free of the planet at a rate of 200,000 tons per second, forming an expansive comet-like tail not previously seen, reported Space.com.

Thanks to its exuding atmosphere, WASP-69b is losing one Earth mass every billion years, which is “quite a bit,” said Tyler, “but for a hot Jupiter, it’s really not that much.”

The new findings are attributed mostly to the Keck Observatory’s large telescope mirror, which collects more light than previous telescopes that observed WASP-69b. But it could also be changing the behavior of the WASP-69 star, which astronomers call stellar variability, Tyler said. “It’s hard to get a handle on exactly what type of variability is going on within the star itself”, as reported by Space.com.

All Credit To: Space.com