Astronomers at the University of California, Los Angeles have made an extraordinary discovery about exoplanet WASP-69 b. The planet is losing its atmosphere slowly over time due to the influence of stellar wind from its host star, resulting in a comet-like tail that extends more than 350,000 miles.
This unique feature occurs because lightweight gases like hydrogen and helium escape from the planet’s outer atmosphere, but are shaped by powerful stellar winds into a tail-like formation. The tail is not only long but also dynamic, changing shape with variations in the stellar wind.
WASP-69 b is classified as a “hot Jupiter,” orbiting extremely close to its star, making its outer atmosphere intensely hot. This heat causes gases to escape into space, creating the tail-like structure. The stellar wind plays a crucial role in shaping the escaping gas, stretching it into a long, comet-like tail.
The discovery of WASP-69 b’s unique tail has significant implications for exoplanet and stellar studies. It highlights the dynamic relationship between planetary atmospheres and stellar activity, providing insights into how these interactions shape the formation and behavior of exoplanetary tails.
Observations suggest that the tail is not only long but also observable, extending more than 7.5 times the radius of the planet or over 350,000 miles. However, its exact length may be longer due to the limitations of current telescopic observations. The study of WASP-69 b’s tail offers a new perspective on exoplanetary science, shedding light on the ever-changing relationship between stellar activity and planetary atmospheres.
Source: https://scitechdaily.com/astronomers-unveil-the-mysterious-350000-mile-tail-of-exoplanet-wasp-69-b