Planetary bodies observed in the habitable zone of a dead star

A planetary debris ring dotted with moon-sized structures has been observed orbiting near a white dwarf – a dead star – 117 light-years away.

A ring of planetary debris with structures the size of a Moon has been observed, for the first time, orbiting close to a dead star , suggesting the existence of a planet  in the habitable zone of that sun, where there could be water and life.

White dwarfs are dead stars , glowing embers of stars that have burned up all their hydrogen fuel, but since they are difficult to observe because of their dimmer luminosity, very little is known about their planetary systems.

Through transit

A study published by the Monthly Notices of the Royal Astronomical Society , led by the British UCL and with the participation of the Instituto Astrofísico de Canarias and the Universidad de la Laguna, has studied the white dwarf WD1054-226, located 117 light years away in the Milky Way .

The team observed, with space and ground-based telescopes, pronounced dips in light corresponding to 65 evenly spaced planetary debris clouds orbiting the star every 25 hours.

The researchers concluded that the precise regularity of the transiting structures suggests that they are held in such a precise arrangement by a nearby planet.

The study’s lead author, Jay Farihi, noted that it is “the first time that astronomers have detected any type of planetary body in the habitable zone of a white dwarf .”

The Moon-sized structures observed are irregular and dusty, similar to a comet, and pass in front of the star with absolute regularity, which is “a mystery that we cannot currently explain,” Farihi said.

One possibility that he described as “exciting” is that these moons are held in such a uniform orbital pattern due to the gravitational influence of a nearby planet, because without it, friction and collisions would cause the structures to spread out, losing precise regularity. that is observed.

The possible existence of a planet in the habitable zone is “exciting and also unexpected; we were not looking for it,” said the researcher, who stressed that “it is important to keep in mind that more evidence is needed to confirm the presence of a planet.”

This is because the putative planet cannot be observed directly, so “confirmation may come from comparing computer models with new observations of the star and orbiting debris.”

The team believes that any planet that could support water and even life “would be a recent development” and that the habitable zone of WD1054-226 would be so for at least 2 billion years, which includes about 1 billion in the future.

More than 95% of the stars end up becoming white dwarfs , in fact, the Sun is expected to do so within a few billion years, so this research -he said- “allows us to glimpse the future of our own system solar”.

The team monitored WD1054-226 for 18 nights using the ULTRACAM high-speed camera attached to the European Southern Observatory’s (ESO) New Technology Telescope (NTT) at La Silla Observatory in Chile.

To better interpret the changes in light, they also examined data from NASA’s TESS satellite, which allowed the researchers to confirm that the planetary structures had a 25-hour orbit. (EFE)