Astronomers have discovered an Earth-sized planet that is showered with so much radiation that its atmosphere has long since eroded away, leaving it bare. Life as we know it couldn’t exist on this hot world, but astronomers are interested in it for another reason: For the first time, they may be able to study the universe. geology For a planet outside our solar system.
Newly discovered Exoplanet, called SPECULOOS-3 b, is a rocky planet about 55 light-years from Earth. It orbits its host star every 17 hours, but the days and nights on this planet are endless. Astronomers suspect that the planet is tidally bound to its star, like the Moon to Earth. The only day side always faces the star, while the night side is locked in eternal darkness.
Telescope observations show recurring radiation from the exoplanet’s star, a 7-billion-year-old red dwarf roughly the size of Earth. Jupiter, roasting the planet to Venus-like temperatures. So any atmosphere the planet may have easily escaped into space long ago and left behind a scorching, airless ball of rock, the astronomers reported in the new study, published May 15 in the journal . Nature astronomy.
“Life as we know it could not have emerged on the planet’s surface – atmospheric or not – because it could not sustain large amounts of water in liquid form,” said the study’s lead author. Michael GillonThe astronomer at the University of Liège in Belgium told Live Science. “It’s like a bare, rocky planet Mercury“.
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Although SPECULOOS-3 b is not life-friendly, astronomers said it is close enough to Earth to conduct detailed follow-up studies of its chemical composition, which will reveal whether the planet is geologically active at all. Notes already planned with James Webb Space Telescope (JWST), for example, will be able to confirm whether volcanoes have erupted on the planet. This would reveal how rocky planets like SPECULOOS-3 b form around faint, lightweight stars and whether some of them are suitable for life despite their proximity to their stars.
Gillon said researchers “extensively searched” for planetary siblings of SPECULOOS-3 b in the same star system but did not find any. He noted that those additional planets may exist but are simply too small or too far from their host star to be seen.
A hot planet around a cold star
Gillon and his colleagues have discovered SPECULOOS-3 b using a network of six telescopes spread across Chile, the Canary Islands and Mexico since 2011. This network is called the Search for Planets Obscuring Ultracool Stars network, or SPECULOOS, which shares its name with a group of stars. Spiced Belgian shortbread is traditionally served to children on December 6 every year for Saint Nicholas Day.
The project’s main goal is to discover rocky planets orbiting ultracool dwarf stars, whose small size makes it easier for telescopes to detect planets orbiting them. In addition to being thousands of degrees cooler than the Sun and hundreds of times dimmer, they burn their fuel more slowly and end up living much longer – about 100 billion years. (The Sun will be about 10 billion years old When you die about 4.5 billion years from now.)
“They are expected to be the last still bright stars in the universe,” said study co-author Amory TriodeA professor of exoplanetary science at the University of Birmingham in England said: statement. Researchers say their extremely long lifespan provides favorable windows for life to emerge on planets within their systems.
However, their extreme weakness makes studying them difficult. To discover SPECULOOS-3 b, the SPECULOOS robotic telescope in Mexico observed apparent dips in the host star’s light continuously for five nights in 2021. The first hints of the newly discovered planet appeared then and were confirmed a year later, according to the study.
“If there was no atmosphere, there would be no blue sky or clouds – it would just be darkness, as there is on the surface of the Earth.” the moon“, co-author of the study Benjamin Rackhama research scientist at the Massachusetts Institute of Technology said in a separate article Statement from MIT. The “Sun” will be a large, purple-red, speckled, glowing star that will appear about 18 times larger than the Sun appears to us in the sky.
SPECULOOS-3 b is the ninth planet found by the project, and the team expects to discover more planets in the coming years, Gillon said. Like planets previously discovered by the project — including a family of seven in the known TRAPPIST-1 system, some of which are considered habitable — the newly discovered SPECULOOS-3 b “is an excellent target for JWST,” Gillon said.
“With this world, we can essentially begin to study the geology of exoplanets,” said study co-author Julian de WitAssistant Professor of Planetary Sciences at MIT said in an MIT statement. “How cool is that?”
