Astronomers Find First Possible Intact Planet Orbiting White Dwarf Star

Scientists Find First Ever Jupiter-Sized Planet Orbiting a Dead Star

White dwarfs release light and heat as they cool down, so a close planet could actually be in the habitable zone of the star, or the Goldilocks area where the temperature on the planet is just right to support liquid water - and even potentially life - on the surface.

It orbits a cool, quiet white dwarf that is roughly 18,000 kilometres across, may be up to 10 billion years old. The same fate awaits more than 90% of the stars in our galaxy.

Astronomers have used the global Gemini Observatory, a Program of NSF's NOIRLab, and other telescopes around the globe and in space to find and characterize a giant planet, less than 13.8 times as massive as Jupiter [1], orbiting a white dwarf star [2][3].

However, the discovery of a planet around a white dwarf raises questions about a unique habitable environment that could exist close to the light of a dying star. The white dwarf is the remnant of a sun-like star, significantly shrunken all the way down to roughly the scale of Earth, but it retains half the solar's mass. For the first time, astronomers have detected a giant planet, about the size of Jupiter, orbiting the dead star.

Vanderburg assumes the WD 1856 b, as the planet was named, used to be at least 150 times farther away from the star compared to its current position.

Their simulations suggested that when the star became a white dwarf, the planet was kicked closer in.

"WD 1856b somehow got very close to its white dwarf and managed to stay in one piece", said Andrew Vanderburg, the lead author of the study published in Nature.

That hot center, Vanderburg clarified, is the thing that we call a white midget - and one of the characterizing attributes of a white diminutive person is that, on account of its solid power of gravity, it will in general force divine bodies toward it and split them up simultaneously.

"We've never seen evidence before of a planet coming in so close to a white dwarf and surviving".

All in all, these findings "could offer a way for a white dwarf to give rise to a second generation of life in a planetary system, long after the star ran out of hydrogen fuel and died", Vanderburg said. The global team, including astrophysicists based in Switzerland, has published its findings in the journal Nature. Read the original article.

Stars like our sun "burn" hydrogen fuel into helium in nuclear fusion reactions, which warms up ours and other planets. Infrared data Lovingly departed Spitzer Space Telescope It says it is 14 times higher than Jupiter. The distinctive construction of white dwarf-planet methods gives a really ideal alternative to check the chemical signatures of orbiting planets' atmospheres, a possible approach to seek for indicators of life from afar. The contributing telescopes included NASA's exoplanet-hunting telescope TESS and two large ground-based telescopes in the Canary Islands. The white dwarf is 40% larger than Earth. "And until now, there weren't any known planets around white dwarfs". The TESS data showed that the star, WD 1856+534, was dimming by half every 1.4 days, signifying that something massive, perhaps a planet, was passing in front of it each time. One orbit is completed in 34 hours - it is 60 times faster compared to Mercury orbiting the Sun. In the process of dying, some stars will drastically expand, becoming a huge "red giant", like Betelgeuse, and engulfing any of the planets orbiting close by. "In this case the planet is bigger than its host star by a factor of 7!" So how did WD 1856 b survive?

Artist's conception of the white dwarf (foreground) and its planet. The team behind the paper believes the gaseous planet was pulled in by the white dwarf's gravity long after the star had dwindled down from its red giant phase - otherwise the planet would have been obliterated in its current orbit.

Siyi Xu, an assistant astronomer at the US National Science Foundation's Gemini Observatory, said that because there was no discernible debris from the planet around the star, researchers concluded it was intact.

"This system therefore opens up an entirely new field of exoplanetary research", he added.



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