Skip to main content

A year on this Jupiter-like planet lasts 18 hours and it’s about to be destroyed

Artist’s impression of a hot Jupiter orbiting close to a star
Artist’s impression of a hot Jupiter orbiting close to a star. University of Warwick/Mark Garlick

Astronomers have located a planet similar to Jupiter that orbits its host star so closely that its year lasts just 18 hours. Planet NGTS-10b is 27 times closer to its star than Mercury is to the sun, and according to the researchers who discovered it, it is “perilously close” to being torn apart.

Located 1,000 light-years away from Earth, this is the shortest-ever orbital period discovered for this type of planet, called a hot Jupiter. The astronomers were able to locate the planet using what is called the transit method, in which they measure the brightness of distant stars and look for regular dips in brightness which indicate a planet is passing between the star and Earth.

“Although in theory hot Jupiters with short orbital periods (less than 24 hours) are the easiest to detect due to their large size and frequent transits, they have proven to be extremely rare,” lead author Dr. James McCormac from the University of Warwick Department of Physics said in a statement. “Of the hundreds of hot Jupiters currently known there are only seven that have an orbital period of less than one day.”

The planet is also tidally locked, which means one side of it always faces toward its star. This contributes to blistering surface temperatures which are estimated to be more than 1,000 degrees Celsius.

The astronomers are curious as to how the planet came to be located so close to a star, and they assume it must have formed elsewhere and migrated inward. “It’s thought that these ultra-short planets migrate in from the outer reaches of their solar systems and are eventually consumed or disrupted by the star,” co-author Dr. David Brown explained. “We are either very lucky to catch them in this short period orbit, or the processes by which the planet migrates into the star are less efficient than we imagine, in which case it can live in this configuration for a longer period of time.”

The long-term outlook for the hot planet is not looking good, as the researchers believe it will eventually be destroyed. “Over the next ten years, it might be possible to see this planet spiraling in,” co-author Dr. Daniel Bayliss said. “The best model that we’ve got suggests that the star is about ten billion years old and we’d assume that the planet is too. Either we are seeing it in the last stages of its life, or somehow it’s able to live here longer than it should.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Europe’s newest planet-hunting satellite opens its eyes for the first time
Artist's impression of CHEOPS

Artist's impression of CHEOPS ESA / ATG medialab

The European Space Agency (ESA)'s new exoplanet-hunting instrument, the CHaracterizing ExOPlanet Satellite (CHEOPS), has opened its eyes to observe the universe for the first time.

Read more
This planet is so hot it tears apart the hydrogen molecules in its atmosphere
KELT-9b

The extreme forces acting on huge planets close to blistering stars lead to unexpected findings like planets shaped like footballs, planets in strange locations, and even a planet that is hotter than most stars. This last finding, the exoplanet KELT-9b, was the target of more research that revealed it is "prone to planetwide meltdowns so severe they tear apart the molecules that make up its atmosphere," according to NASA.

KELT-9b is three times the mass of Jupiter and has an almost unbelievable surface temperature of 7,800 degrees Fahrenheit (4,300 degrees Celsius), making it the hottest planet discovered so far. It is this extreme heat that leads to the breakdown of molecules of hydrogen in its atmosphere.

Read more
This giant planet is being evaporated as it orbits its long-dead star
white dwarf giant planet artist  s impression of the wdj0914 1914 system

This illustration shows the white dwarf WDJ0914+1914 and its Neptune-like exoplanet. Since the icy giant orbits the hot white dwarf at close range, the extreme ultraviolet radiation from the star strips away the planet’s atmosphere. While most of this stripped gas escapes, some of it swirls into a disc, itself accreting onto the white dwarf. ESO/M. Kornmesser

Astronomers have been finding planets in all sorts of unexpected locations recently. First, NASA's planet-hunting satellite TESS discovered a planet that should have been annihilated by its star. Then, there was the news that planets could form around supermassive black holes. And now, a team from the European Southern Observatory has seen evidence of the first giant planet orbiting a white dwarf -- the decayed remnants of a once-bright star which is evaporating the planet as it fades.

Read more