Meet WASP-69b, the giant-tailed exoplanet

A group of researchers from the University of California, Los Angeles (UCLA) in the USA has detailed the impressive details of the exoplanet WASP-69b in a study published in the scientific journal Astrophysical Journal. It has a huge tail, almost the size of Jupiter, resembling that of a speeding comet; but it is tightly coupled to the orbit of its host star.

In addition to being about the same size as Jupiter, the exoplanet also consists of gas. In the article, scientists explain the origin of this distinctive tail as follows: It occurs when the atmosphere of a celestial body ‘escapes’ into space. Thus, intense stellar winds shape this structure, giving the planet a strange comet appearance.

In the official statement, researchers revealed that the tail of the exoplanet extends to approximately 563 thousand kilometers; the total is equivalent to seven times the size of the planet itself. Before this study, it was unclear whether it had a small tail or was an ordinary exoplanet.

“Studies by previous groups showed that this planet had lost some of its atmosphere and showed a thin tail or perhaps none at all. But we have now pinpointed this tail and shown that it is at least seven times larger than the planet itself,” said UCLA doctoral student and Dakotah Tyler, lead author of the study.

WASP-69b’s giant tail

Scientists observed that WASP-69b’s atmosphere consists mainly of hydrogen and helium; giant tail is ‘blown’ towards Earth by winds and radiation from its star. Based on this, the researchers were able to calculate how much mass the planet had lost.

“With a mass approximately 90 times that of the Earth, WASP-69b has such a large reservoir of matter that even losing this enormous amount of mass will not affect it much during its lifetime. There is no danger of losing its entire atmosphere during the formation of its star. This planet is so extreme and His resilience in a hostile environment serves as a powerful reminder to us all,” adds Tyler.

Although astronomers discovered details about the tail in this study published in January 2024, the discovery of WASP-69b occurred in 2013.

The exoplanet is so close to its star that it completes its orbit in just four days. By comparison, it takes Earth 365 days to make a complete revolution, while Mercury, the planet closest to the Sun, takes 88 days to make a complete revolution.

Get up-to-date information about astronomy at TecMundo. If you wish, take the opportunity to understand how NASA discovered 17 exoplanets with habitable oceans and geysers. Until next time!