A newly discovered exoplanet has surprisingly warm surface temperatures and suddenly becomes one of the most interesting objects in our immediate vicinity. This Venus-sized rocky world passes through a red dwarf star, giving astronomers a rare opportunity to study whether such a planet could retain an atmosphere and potentially support life. .
Gliese 12b is comparable in size to Venus but slightly smaller than Earth, orbiting its cool red dwarf star, Gliese 12, at just 7% of the distance that Earth is to the Sun. This eerily close proximity means that over a year of just 12.8 days, the planet receives 1.6 times as much energy from its star as Earth does from the Sun. Despite this, Gliese 12b’s surface temperature is estimated at 107 degrees F (42 degrees C), making it a temperate world and one of the coolest exoplanets ever discovered, say the new research team. the study Published today in the Monthly Notices of the Royal Astronomical Society. In comparison, on Earth average surface temperature The maximum temperature is 59 degrees Fahrenheit (15 degrees Celsius), but it is rising due to human-induced climate change.
The next big step for astronomers is to determine whether Gires 12b, 40 light-years from Earth, has an atmosphere, and if so, what type of atmosphere it has, and whether the planet’s surface can support stable liquid water (a prerequisite for life as we know it). “Gires 12b is one of the perfect targets to study whether Earth-sized planets orbiting cool stars can retain atmospheres, a key step in improving our understanding of planetary habitability across the galaxy,” Shishir Dholakia, a doctoral student at the Centre for Astrophysics at the University of Southern Queensland in Australia, explained in an emailed statement.
The host star, Gliese 12, is about 27% of the Sun’s mass and its surface temperature is about 60% of that of its host star. Unlike many red dwarfs known for their magnetic activity and frequent, powerful X-ray flares, Gliese 12 shows no such signs. extreme actionAstronomers say they are growing hopeful that Gliese 12b’s atmosphere may still be intact.
The exoplanet’s atmosphere, which may or may not exist, will be a major focus of future research, especially with the James Webb Telescope. The James Webb Telescope’s advanced infrared capabilities make it ideal for analyzing the chemical composition of planetary atmospheres. The exoplanet Gliese 12b frequently passes in front of its host star when viewed from Earth, making it possible to observe it in detail using transit spectroscopy. This method allows astronomers to study the light filtered through a planet’s atmosphere, revealing the presence of various gases and potential indicators of habitability.
“While we don’t yet know if it has an atmosphere, it is thought to be an extrasolar Venus, with a similar size to our solar system neighbors and similar energy intake from its star,” said Masayuki Kuzuhara, a project assistant professor at the Astrobiology Center in Tokyo. “We’ve discovered the closest transiting, temperate, Earth-sized planet to date,” he added.
The planet’s location and characteristics could provide insight into why Earth and Venus have vastly different atmospheres, despite their similarities. Dholakia explained: “The atmosphere traps heat, which varies by type. [of atmosphere]—Actual surface temperatures can vary significantly.”
In the study, the researchers refer to an exoplanet’s “equilibrium temperature,” or its temperature in the absence of an atmosphere. The primary scientific interest in Gliese 12 b is to understand what kind of atmosphere it has. Ideally, Gliese 12 b would have an Earth-like atmosphere, not the dense, toxic clouds of sulfuric acid of Venus, whose surface temperature exceeds 860 degrees Fahrenheit (450 degrees Celsius). Dholakia said Gliese 12 b gets a similar amount of light to Earth and Venus, so studying it could help scientists understand more about the differences between the two planets in our solar system.
The researchers used NASA’s Transiting Exoplanet Survey Satellite (TESS) and the European Space Agency’s CHEOPS (CHARacterising ExOPlanets Satellite) to estimate the equilibrium temperature of Gliese 12 b. TESS initially detected planets by observing transits, the periodic dimming of a star’s light caused by a planet passing in front of its host star. These observations were then followed up with more precise measurements by CHEOPS, which helped refine the planet’s orbital period and radius. By combining data from TESS and CHEOPS, researchers were able to calculate the equilibrium temperature by evaluating the amount of starlight a planet receives and its distance from the star. The project was a collaboration between teams from the University of Southern Queensland, the University of Edinburgh and the University of Tokyo Astrobiology Center.
The significance of this discovery extends beyond the solar system: it may help indicate whether most stars in our Milky Way galaxy, which are cool red dwarfs, could host temperate planets with atmospheres and could be habitable. was suggested It is thought that there may be as many as 4.5 billion potentially habitable planets orbiting red dwarf stars in our galaxy, but little evidence exists to support this.
Related article: How life could survive on the exoplanet Proxima b
The discovery of Gliese 12 b highlights astronomers’ progress in the search for habitable planets. The closest exoplanet to Earth, Proxima Centauri b, is only 4 light-years away and is still poorly understood due to its non-transiting nature. Meanwhile, Gliese 12 b’s transiting behavior provides a clear avenue for studying its atmosphere. This advantage is expected to allow scientists to gain deeper insight into its potential habitability.
As research continues, Gliese 12 b could play a pivotal role in the quest to understand the conditions necessary for life outside our solar system.
more: The real physics behind Netflix’s ‘Three-Body Problem’
