Ultracool dwarf stars are widespread near the Sun. Despite this, due to its extremely low brightness, its planetary population remains largely unexplored, and only one such planetary system, TRAPPIST-1, has been confirmed to exist so far. is.and astronomer speculoos (Search for Planets Eclipsing Ultra-Cool Stars) project has detected an Earth-sized planet orbiting the nearby ultra-cold dwarf star SPECULOOS-3 for 17 hours.
speculoos-3 It is an M6.5 spectral dwarf star located 16.8 parsecs (55 light years) away in the constellation Cygnus.
The star, also known as LSPM J2049+3336 and TIC 230741378, is not only more than twice as cold as the Sun, but also 10 times less massive and 100 times brighter.
“We designed SPECULOOS specifically to observe nearby ultracold dwarf stars in search of rocky planets suitable for detailed study,” said Dr. Michael Guillon, an astronomer at the University of Liège.
“In 2017, our SPECULOOS prototype using the TRAPPIST telescope discovered the famous TRAPPIST-1 system, which consists of seven Earth-sized planets, some of which are potentially habitable. It was a great start!”
The newly discovered exoplanet, named SPECULOOS-3b, orbits its parent star every 17 hours.
The alien world is likely tidally locked, with its dayside always facing the star, which has an average temperature of about 2,600 degrees Celsius.
Because of its short orbit, SPECULOOS-3b receives nearly twice as much energy every second as Earth receives from the sun, literally bombarding it with high-energy radiation.
“SPECULOOS-3b is virtually the same size as our home planet,” Dr. Gillon said.
“One year, or one orbit around the star, lasts about 17 hours. On the other hand, day and night should never end. We know that because the planets rotate in sync, the moon We believe that the same side, called the day side, always faces the stars, while the night side is closed in endless darkness.
Professor Amaury Tryaud, from the University of Birmingham, said: “The discovery of SPECULOOS-3b shows that our global network is working well and is poised to detect even more rocky worlds orbiting ultra-low mass stars. It shows,” he said.
“Although ultracold dwarfs are cooler and smaller than the Sun, their lifetimes are more than 100 times longer (about 100 billion years) and they are expected to be the last stars still shining in the universe.”
“This long lifespan could provide an opportunity for extraterrestrial life on the orbiting planet to develop.”
“The small size of ultracool dwarfs makes it easier to detect small planets,” said Dr. Birmingham, an astronomer at the University of Birmingham.
“SPECULOOS-3b is special in that its stellar and planetary properties make it a perfect target for Webb, which can provide information about the composition of the rocks that make up its surface.”
of study It was published in the magazine natural astronomy.
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M. Gillon other. An Earth-sized exoplanet orbiting the nearby ultracool dwarf star SPECULOOS-3 has been detected. Nat Astron, published online on April 10, 2024. doi: 10.1038/s41550-024-02271-2
Source: www.sci.news
