Astronomers have discovered an exoplanet with a giant comet-like tail. The planet, known as WASP-69b, is slowly being vaporized by the radiation from its host star.
WASP-69b is a gas giant planet that orbits very close to its host star, meaning it is a type of planet often referred to as a hot Jupiter. That alone isn’t all that interesting. These are some of the most commonly found exoplanets out there, as their size and proximity to the star make them easy to detect.
But what’s strange about WASP-69b is its long, luxurious tail, like a giant comet. Intense radiation from the star, or stellar wind, not only boils the planet’s atmosphere, but sweeps it away in long streams like the tail of a comet.
In a new study, astronomers used Hawaii’s KECK Observatory to examine WASP-69 b in more detail, revealing the full extent of its tail. As a result, its length was found to be about 580,000 kilometers (360,000 miles). This is about 1.5 times the distance from the Earth to the Moon.
“Previous work by our research group has shown that the planet is losing some of its atmosphere, suggesting the presence of a subtle tail or no tail at all,” said lead author of the study. said one Dakota Tyler. “But we conclusively detected this tail and showed that it is at least seven times longer than the planet itself.”
The researchers say “at least” because they ran out of observation time before they could actually see the end of the tail. We don’t know how far it actually extends, but in any case it could change over time depending on changes in the stellar wind.
WASP-69b appears to be losing gas (mainly hydrogen and helium) at a rate of about 200,000 tons per second. Although it sounds like we’re depleting it rapidly, we’re losing about the mass of one Earth about every billion years. This means that over its estimated lifetime so far, Earth has lost the equivalent of about two Earths worth of gas. And there’s a lot more where that gas came from.
“WASP-69b, which has a mass about 90 times that of Earth, stores so much material that even if it loses this huge amount of mass, it will not have a significant impact over its lifetime,” Tyler said. said. “There is no danger of losing the entire atmosphere during this star’s lifetime.”
This research was published in ‘The Astrophysical Journal’. You can see the tail animation in the video below.
WASP 69b 2K
Source: UCLA, NASA
