White dwarf J1328−1450 has two rings of planetary debris
A white dwarf surrounded by two distinct rings of planetary debris may offer a glimpse of what remains after a star like the Sun dies.
A white dwarf surrounded by two distinct rings of planetary debris may offer a glimpse of what remains after a star like the Sun dies. Astronomers say the rare arrangement appears to be shaped by two surviving planetary bodies.
The system, centered on the white dwarf J1328−1450, was observed using the European Southern Observatory’s Very Large Telescope. Its debris disc has two parts separated by a clear gap, unlike the discs seen in similar systems previously found.
Clues to surviving planets
The debris consists of material left over from planets that once orbited the star. The researchers say two planetary bodies may be shaping the rings; one could be as large as Pluto.
“We have known for some time that planets may survive beyond the transformation of their central star, but this is the first example of a complex system with a double debris disc and potentially two surviving planetesimals,” said Nicola Gentille Fusillo, an astronomer at the University of Trieste and lead author of the study.
The findings, published in Nature Astronomy, add evidence that some planetary bodies can endure the changes that turn a Sun-like star into a white dwarf. The two-ring structure offers a more complex picture than previously observed debris discs around these stellar remnants.
A possible future for the Solar System
Billions of years from now, the Sun is expected to run out of fuel and expand into a red giant before shedding its outer layers. That process will destroy some planets, while others may survive; the remaining dense core will become a white dwarf.
J1328−1450 is the burnt-out core left by a star similar to the Sun. Its debris rings provide a view of planetary material around such a remnant, and may help researchers understand how planetary systems change as their stars reach the end of their lives.
