Astronomers have made new observations that may offer clues into how a giant exoplanet survived the violent death of its host star. The findings could serve as a preview of the fate that may await our solar system’s largest planets when the sun dies in 5 billion years.

WD 1856 b: A Baffling Exoplanet

Located 80 light-years from our planet, WD 1856 b is a Jupiter-size planet that orbits a dead white dwarf star. The planet is seven times larger than its Earth-size star and completes one orbit around the dead star every 34 hours.

When a massive sunlike star exhausts the hydrogen fuel at its core, it puffs up to more than 100 times its size before collapsing into a dense white dwarf. Given the close proximity of WD 1856 b to its star, astronomers were unsure how the planet survived its host’s destruction.

Retracing WD 1856 b’s Journey

To retrace WD 1856 b’s unlikely journey of survival, astronomers used the James Webb Space Telescope to capture the latest glimpses of the planet and measure its atmosphere, mass, and temperature. The team’s data suggests that huge planets can survive the demise of their host stars in ways previously thought impossible.

The planet’s tight orbit and the lopsided relative sizes of WD 1856 b and its host star motivated astronomers to investigate further. The team combined new measurements with models of how giant planets like Jupiter and Saturn cool over time, which occurs at a predictable rate related to their mass.

The results showed that the planet originally orbited the star from a safer, much greater distance. But WD 1856 b heated up while migrating inward after the star died. The researchers have two competing theories about how WD 1856 b ended up in its current, tight orbit.

Original reporting: El Paso News (HLL/CB) — read the source article.