The mysterious planet causes the orbiting star to age

NASA's Chandra X-ray Observatory has discovered an anomalous planet that has the ability to make its star around older than its actual age.

The star called WASP-18, about the same size as the Sun and the planet orbiting it, is WASP-18b located 330 light-years from Earth. Astronomers were surprised when WASP-18 showed signs of an old star and thought its planet was the cause of this phenomenon.

WASP-18b is a planet 10 times larger than Jupiter and completed a spin around the host star in less than 23 hours. Therefore, it is classified as "Hot Jupiter" in classifying extraterrestrial planets (planets outside the solar system).

The star named WASP-18 makes the star around me faster.(Source: NASA)

WASP-18b is the first orbiting planet known for its ability to make its host star older than its true age. Ignazio Pillitteri, an astronomer at the Palermo Astronomical Observatory in Italy, said the researcher said:

"WASP-18b is an extreme extraterrestrial planet . It is one of the largest known" Hot Jupiter ", and is also one of the planets closest to its host star. "This leads to unpredictable behavior. This planet is making the host star older than its true age."

Pillitteri's team determined that the WASP-18 star is about 500 million to 2 billion years old, based on theoretical models and other data. According to astronomical standards, this star is quite young. If compared to WASP-18, our Sun is about 5 billion years old and has gone half its life.

Young stars are more active, emitting stronger magnetic fields and more sparks, as well as releasing denser X-rays than older stars. These activities are related to the star turning around itself, and will gradually decrease in intensity as the star ages. However, after observing WASP-18 at the Chandra Observatory, astronomers could not detect any X-rays from this star.

Based on the relationship between magnetic activity and the release of X-rays by stars, as well as the true age of WASP-18, they claim this star is about 100 years less active than it really is.

"We think that the orbiting planet is making an aging star by destroying the star's internal structure," co-author Scott Wolk, of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, said. know.

The researchers suggest that the tidal force caused by the gravitational attraction of the planet WASP-18b is similar to the effect of the Moon on the tide on Earth, but to a much greater degree may have broken from school of stars. The strong or weak magnetic field depends on the convection of the star, or the hot gas moving strongly or weakly in its core.

"The gravity of the planet can weaken the activity of gas in the core of the star, creating a domino effect that causes the magnetic field to decline and become an old star , " co-author Salvatore Sciortino of the Observatory. Astronomical survey Palermo in Italy said.