Astronomers have discovered over 5,500 worlds out there in the great unknown. And yet, they continue to baffle and surprise us. The latest surprise comes in the form of exoplanet WASP-69B, a planet with a 350,000-mile-long comet-like tail flowing behind it.
Slightly larger than Jupiter, WASP-69b is what astronomers often refer to as a hot Jupiter. It’s less dense than our solar system’s largest gas giant and orbits its star in just 3.9 Earth days. While WASP-69b might be one of the most common types of exoplanet, its massive tail is far from ordinary.
It is this tail that really drew astronomers to the exoplanet. Upon closer observation, they discovered that the tail is actually the planet’s atmosphere leaking out of it and getting caught up in the stellar winds created by its star. It’s a wonderfully unique sight and one that has caused the matter being ripped from the planet to become shaped like a comet’s tail.
The researchers estimate that WASP-69b could be shedding up to 200,000 tons of mass every second. Despite that rate, though, the researchers theorize that the planet will retain most of its atmosphere throughout the star’s lifetime.
That makes the planet and its comet-like tail exceptionally intriguing points of observation, especially since we have found other planets with tails. Most of those are also hot Jupiters and are all found relatively close to their stars, which is part of what causes the tails to be created in the first place.
But the loss of atmospheric mass is a universal feature, the researchers explain. WASP-69b is a perfect opportunity to see it in action and to easily study it from fairly close up. Not to mention, this exoplanet could help us learn more about planetary formation in such unique scenarios.
Perhaps one day, this exoplanet and its mysterious and beautiful tail will help define a new generation of space exploration and discoveries. And, if nothing else, it will keep astronomers busy for a while. These latest discoveries are outlined in a study featured in The Astrophysical Journal.