It is no secret that the Sun will expand, its surface eventually will be passed where Earth’s orbit is now. So the expanding star will engulf and destroy the Earth; however, it will happen in about 5 billion years. Not the same can be said about the exoplanet WASP-12b.
The exoplanet is located 600 light-years away in the constellation Auriga and is more unlucky than our home planet. A Princeton-led team of astrophysicists has discovered that this exoplanet is spiraling in toward its Sun, heading toward its destruction in about 3 million years. Exoplanet WASP-12b is a giant gaseous planet similar to Jupiter, orbiting its host star in just 26 hours. Compared to Earth, we take 365 days to orbit, which is significantly a lot slower.
“Ever since the discovery of the first ‘hot Jupiter’ in 1995 — a discovery that was recognized with this year’s Nobel Prize in Physics — we have wondered how long such planets can survive,” said Joshua Winn, a professor of astrophysical sciences at Princeton and one of the authors of the paper.
Doomed Exoplanet Is Heading Toward Its Host Star
“We were pretty sure they could not last forever. The strong gravitational interactions between the planet and the star should cause the planet to spiral inward and be destroyed, but nobody could predict how long this takes. It might be millions of years, it might be billions or trillions. Now that we have measured the rate, for at least one system — it’s millions of years — we have a new clue about the behavior of stars as fluid bodies,” Winn said.
“If we can find more planets like WASP-12b whose orbits are decaying, we’ll be able to learn about the evolution and eventual fate of exoplanetary systems,” said first author Samuel Yee, a graduate student in astrophysical sciences. “Although this phenomenon has been predicted for close-in giant planets like WASP-12b in the past, this is the first time we have caught this process in action.”
“These new data strongly support the orbital decay scenario, allowing us to firmly say that the planet is indeed spiraling toward its star,” said Yee. “This confirms the long-standing theoretical predictions and indirect data suggesting that hot Jupiters should eventually be destroyed through this process.”