'-87 degree celsius': NASA's James Webb Telescope discovers coldest ever exoplanet in 'forbidden zone'
Breakthrough
In a remarkable scientific breakthrough, scientists , with the help of NASA’s James Webb Space Telescope (JWST) have confirmed the discovery of the coldest exoplanet ever observed, orbiting a white dwarf. Named WD 1856+534 b, this Jupiter-sized gas giant lies approximately 80 light-years from Earth.
First detected in 2020
First identified in 2020, WD 1856+534 b orbits a dead star, or white dwarf, every 1.4 days. It was previously unclear whether the object was a planet or a brown dwarf, as limited data from the retired Spitzer Space Telescope made classification uncertain.
JWST confirms temperature and identity
New measurements from JWST’s mid-infrared instrument (MIRI) confirmed the object’s status as a planet and revealed its surface temperature to be -87 degree celsius, the coldest ever directly observed in an exoplanet.
Breaks cold record set by Epsilon Indi Ab
This frigid temperature beats the previous record-holder, Epsilon Indi Ab, which has a temperature of around 2 degree celsius. “We were all a bit surprised – and excited – to find that it was, in fact, a planet, and a really cold one at that,” said Mary Anne Limbach, the study’s lead astronomer to Space.com.
Planet survives star’s destruction
The planet’s presence in the so-called “forbidden zone” — a region close to a white dwarf where planets are expected to be destroyed — has intrigued scientists and suggests some planets can survive or migrate inward after a star’s violent death.
Super-Jupiter with unusual orbit
The study also revealed that WD 1856+534 b has a mass no greater than six times that of Jupiter. Its proximity to the white dwarf defies conventional understanding of orbital dynamics in post-stellar systems.
Second observation planned for july
Limbach and her team plan a second JWST observation this July. By tracking the system's movement relative to background stars, they aim to detect other planets bound to the white dwarf.