The formation process of a white dwarf destroys nearby planets, yet a team of astronomers has located, for the first time, what could be a large planet orbiting around a star of this type, according to a study published this Wednesday Nature.
The investigation, which is signed, among others, by Spanish scientistsof the Instituto Astrofísico de Canarias (IAC), used data from NASA’s TESS satellite, the now-retired Spitzer space telescope and the Gran Telescopio de Canarias (GTC).
The object that astronomers consider to be a planet has been called WD 1856 b, It is very large – about the size of Jupiter – and orbits the star every 34 hours, about 60 times faster than Mercury around the Sun.
The white dwarf destroys the approaching planets
The star, however, She is a cool and calm white dwarf much smaller than the planet, it is about 18,000 km in diameter, can be up to ten billion years old, and is a distant member of a triple star system in the constellation Draco.
The process of creating a white dwarf destroy the nearby planets, and anything that then gets too close is usually ripped apart by the star’s immense gravity.
As such, lead author Andrew Vanderburg of the University of Wisconsin-Madison (USA) noted that they still have “many questions about how WD 1856 b got to its current location. without suffering one of those fates. ” The team believes that “somehow” the object, which was detected by TESS “came very close to its white dwarf and managed to stay in one piece.”
When a star similar to the Sun runs out of fuel, swells up to hundreds or thousands of times its original size, forming a cooler red giant star, explains the IAC in a statement. Subsequently, it expels its outer layers of gas, losing up to 80% of its mass, and the remaining hot core turns into a white dwarf.
The IAC researcher and co-author of the article Felipe Murgas explained that any nearby object is swallowed and incinerated during this process, which in this system would have included WD 1856 b in its current orbit. Therefore, the team considers, according to Murgas, that it is possible that the planet originated at least 50 times further from its current location.
Astrophysicists know that long after the birth of white dwarfs, small distant objects such as asteroids and comets can scatter towards these stars, which usually end up turned into rubble by the gravity of the white dwarf.
How did the WD 1856 b get there?
The team suggests various scenarios that could have pushed WD 1856 b onto an elliptical path around the star, a trajectory that would have become more circular over time as gravity stretched the object, creating huge tides that dissipated its orbital energy.
Finding a possible world that orbits close to a white dwarf has led researchers to consider the implications for studying the atmospheres of small rocky worlds andThese are similar situations, since the tiny size of the white dwarf makes it easier to characterize the planet’s atmosphere.
There is currently no evidence to suggest that there are other worlds in the system, but it is possible that there are additional planets that have not yet been detected