Astronomers Discover Potential Hot Jupiter Locked In A ‘Death Spiral’ Around Its Star

Orbiting a young star nearly 1,100 light-years from Earth lies what may be one of the youngest alien planets ever detected. However, this young exoplanet candidate, which scientists believe is probably a “hot Jupiter” — a term used to describe large planets locked in an extremely close orbit around their parent stars — is doomed from the start.

According to a paper that has been submitted for publication in the Astrophysical Journal, this planet, which orbits its parent star every 11 hours, is locked in a slow “death spiral” that will eventually tear it to shreds.

“A handful of known planets are in similarly small orbits, but because this star is only 2 million years old this is one of the most extreme examples,” lead author Christopher Johns-Krull from the Rice University in Texas, according to whom there is “compelling evidence” that this planet exists, said in a statement released Thursday.

“We don’t yet have absolute proof this is a planet because we don’t yet have a firm measure of the planet’s mass, but our observations go a long way toward verifying this really is a planet,” he added. “We compared our evidence against every other scenario we could imagine, and the weight of the evidence suggests this is one of the youngest planets yet observed.”

The researchers believe that the planet — named PTFO8-8695 b — is slowly losing its outer layers, which are being mercilessly ripped off by the gravity of the parent star. The planet is almost twice the mass of Jupiter but is only 3 to 4 percent the size of the star it orbits.

Although scientists have observed planets trapped in extremely close orbits around their parent stars, this discovery, if confirmed, would be the first time such a planet has been detected in a star system so young.

“We don’t know the ultimate fate of this planet,” Johns-Krull said in the statement. “It likely formed farther away from the star and has migrated in to a point where it’s being destroyed. We know there are close-orbiting planets around middle-aged stars that are presumably in stable orbits. What we don’t know is how quickly this young planet is going to lose its mass and whether it will lose too much to survive.”