World
India
In a groundbreaking discovery, NASA’s James Webb Space Telescope (JWST) has confirmed the existence of the first known planet orbiting a white dwarf—an extinct star. Named WD 1856+534 b, this exoplanet has also earned the title of the coldest planet ever directly observed.
This unusual planetary system lies around 80 light-years from Earth, and the planet completes an orbit around its dead host star in just 1.4 days. The planet was initially spotted in 2020, but only recent observations from JWST have confirmed its true nature.
A Cold Survivor in a Dangerous Zone
With a surface temperature of -87°C, WD 1856+534 b is far colder than any other exoplanet directly imaged to date. It surpasses the previous record-holder, Epsilon Indi Ab, which has a temperature of about 2°C.
What makes the planet’s existence particularly astonishing is its location. It resides in a “forbidden zone” a region so close to a white dwarf that any planet nearby should have been destroyed when the original star expanded into a red giant.
Mary Anne Limbach, an astronomer at the University of Michigan who led the study, expressed her surprise: “This planet defies expectations. It proves that worlds can survive a star’s explosive death and might even migrate into new, tighter orbits afterward.”
Revisiting Planetary Evolution
Earlier data from the Spitzer Space Telescope was not enough to classify the object due to a lack of temperature and mass data. However, JWST’s advanced instruments allowed astronomers to accurately measure both, verifying that WD 1856+534 b is a Jupiter-sized gas giant.
This discovery forces astronomers to rethink theories about what happens to planets when their stars die. It opens the door to understanding the evolution of planetary systems in their final stages.
What’s Next?
Limbach and her research team have plans for a follow-up JWST observation this July. They aim to study the motion of the white dwarf system relative to background stars to see if other planets might also be orbiting it.
These future observations could help scientists understand whether WD 1856+534 b moved closer after the star’s death or formed in that position through unknown processes.
“This is just the beginning,” Limbach said. “Studying such systems helps us place our own solar system in a broader galactic context.”
ALSO READ: Super-Earths More Common Than Expected, New Study Reveals Using KMTNet Discovery
