Scientists have made an amazing and baffling discovery: an “alien world” nearly 10 times bigger than Jupiter which orbits a massive pair of extremely hot stars, defying previous knowledge about how planets are formed.
The mysterious and humongous gas planet is one of the heaviest ever found and was discovered in the Centaurus constellation roughly 325 light years away, according to research published Wednesday in the prestigious science journal Nature.
The planet, dubbed “b Centauri (AB)b” or “b Centauri b,” was formed in an environment that astronomers previously believed was far too inhospitable for planets to form in. The b Centauri two-star system has at least six times the mass of the sun and is the hottest and largest planet-hosting system known so far.
“Until now, no planets had been spotted around a star more than three times as massive as the Sun,” wrote the European Southern Observatory, which captured images of the planet from the Very Large Telescope in the desert of Chile.
1/ Our Very Large Telescope has captured a direct image of a planet orbiting b Centauri the hottest and most massive planet-hosting star pair found to date!
— ESO (@ESO) December 8, 2021
🔗 https://t.co/jM8TQVyZgB
Credit: @ESO /Janson et al. pic.twitter.com/5Dx18AyUEa
Until now, astronomers had no knowledge of planets around a star over three times bigger than the sun.
“The planet in b Centauri is an alien world in an environment that is completely different from what we experience here on Earth and in our Solar System,” said study co-author Gayathri Viswanath of Stockholm University in a statement.
“It’s a harsh environment, dominated by extreme radiation, where everything is on a gigantic scale: the stars are bigger, the planet is bigger, the distances are bigger,” Viswanath added.
Study leader Markus Janson, also of Stockholm University, noted that the discovery “completely changes the picture about massive stars as planet hosts.”
The intense temperature of the system means that it gives off tremendous amounts of ultraviolet and X-ray radiation that typically counteracts the processes that form planets.
“B-type stars are generally considered as quite destructive and dangerous environments, so it was believed that it should be exceedingly difficult to form large planets around them,” Janson said.
3. The planet is about ten times heavier than Jupiter and orbits b Centauri at 100 times the distance Jupiter orbits the Sun. This is one of the widest orbits yet discovered and could be key to the planet’s survival.
— ESO (@ESO) December 8, 2021
Credit: @ESO /L.Calçada/spaceengine.org pic.twitter.com/GFb5cwAXe6
However, the new discovery shows that even such harsh star systems filled with radiation can support the formation of planets.
The observatory noted that the planet’s orbit is “one of the widest yet discovered,” a staggering 100 times greater than the distance between Jupiter and our own solar system’s star. “This large distance from the central pair of stars could be key to the planet’s survival,” it said.
“Our results show that planets can reside in much more massive stellar systems than what would be expected from extrapolation of previous results,” the scientists added.
The astronomers say that the planet may have formed in an unconventional manner, either forming elsewhere before arriving at its present location or through a process of gravitational instability.
“It will be an intriguing task to try to figure out how it might have formed, which is a mystery at the moment,” Janson said.