One of the fluffiest exoplanets we have ever found in the Milky Way galaxy challenges our understanding of how giant planets form.
It is called WASP-107b, tearing an orange dwarf star 211 light-years away, and was already named one of the lowest-density exoplanets when it was discovered in 2017. A new study reveals show that the puffy planet is even more puffier than astronomers thought. .
That means his heart is much lower than originally measured, a finding that could have a major impact on exoplanet research as a whole.
“This work addresses the basic foundations of how giant planets can grow and flourish,” said astronaut Björn Benneke of the University of Montreal, Canada.
“It provides concrete proof that a large gas envelope collection can be stimulated for lower-than-expected rights. “
Super-puff planets, as low-density planets are known, are very rare and strange. They are the size of gas giants, but the density is much, much lower. WASP-107b is pretty puffy. The exoplanet is just slightly smaller than Jupiter, but its mass is below 10 percent of Jupiter, resulting in a density of just 0.13 grams per cubic centimeter.
The exoplanet is also dangerous near its host star. It has an orbital time of just 5.7 days, so close to 736 Kelvin (462 degrees Celsius, or 865 degrees Fahrenheit), and the sensation is accelerating.
The new research, led by physicist Caroline Piaulet from the University of Montreal, redeveloped the mass of WASP-107b using four years of observations made by the Keck Observatory to measure the extent to which the star in response to the gravity thatch of the exoplanet.
Then, using this new calculation, the team analyzed in detail the structure of WASP-107b. To their great surprise, they discovered that the hard core of the exoplanet could not exceed about 4.6 times the mass of the Earth. This would mean that more than 85 percent of the exoplanet’s mass is in its puffy atmosphere.
That’s not so weird, by itself; Jupiter’s heart is thought to be about 5 to 15 percent of the planet’s mass. But Jupiter is bigger overall, and that means his heart is bigger, too. Jupiter is also far from its star. This raises a lot of questions.
“How could a planet with such a low density exist? And how did it keep its large amount of gas from escaping, especially given how close the planet was to its star?” Piaulet said. “This inspired us to do a detailed study to find out what the creative history was.”
So far, our understanding of the creation of gas giants has been based primarily on the easiest to study: Saturn and Jupiter.
They both have conky coriander colliding at more than 10 times the mass of the Earth, so astronomers believed that such a large heart was necessary for the creation of a gas giant. It would provide most of what is needed to awaken circulation and the faster accumulation of gas and dust, before there is enough of it in a protoplanetary disk of material orbiting a new star. -birth.
But there are ads in the WASP-107 system that indicate a possible creation path for WASP-107b. The lower heart mass could be one. The fact that the exoplanet is evolving, noting that it would be much more difficult for it to form in the current dense orbit.
And there is another discovery made by the team. In their long observations of the star, they found evidence of a second exoplanet – WASP-107c – far beyond, on a 1,088-day orbit. That orbit is also very unusual, or oval in shape, showing an interaction of gravity with another body – possibly a WASP-107b baby.
“For WASP-107b, the most plausible scenario is that the planet created far away from the star, where the gas in the disk is cold enough that gas accumulation can occur very quickly,” the astronaut said. Eve Lee of McGill University in Canada.
“The planet has been able to migrate into its normal state, either through interaction with the disk or with other planets in the system.”
The team believes that WASP-107b may be one of the best examples of an exoplanet that came very close to runaway collection before the process was stopped, possibly by interaction with WASP-107c , which moved in towards the star.
This could make it an excellent exoplanet for studying how big a heart needs to be in order to stimulate the formation of gas giants. The team plans to revisit WASP-107b with more sensitive instruments to help solve this mystery.
“Exoplanets like WASP-107b that have no analogue in our Solar System will allow us to better understand the mechanisms involved in planet formation in general and the resulting mix of exoplanets,” Piaulet said. “We are encouraged to examine them in detail.”
The research was published in The Astronomical Journal.