US space agency NASA has discovered a potentially habitable planet located some 40 light years away from Earth.
Dubbed Gliese 12 b, the celestial body has been classified as a "super Earth exoplanet" and is 3.87 times the size of Earth.
The National Aeronautics and Space Administration announced in a news release that the discovery was made through its James Webb telescope.
"Using observations by NASA’s TESS (Transiting Exoplanet Survey Satellite) and many other facilities, two international teams of astronomers have discovered a planet between the sizes of Earth and Venus only 40 light-years away. Multiple factors make it a candidate well-suited for further study using NASA’s James Webb Space Telescope," it said.
Exoplanets are planets that orbit stars outside of our solar system.
"We’ve found the nearest, transiting, temperate, Earth-size world located to date," Masayuki Kuzuhara, a project assistant professor at the Astrobiology Center in Tokyo, said in a statement.
Kuzuhara added, "Although we don’t yet know whether it possesses an atmosphere, we’ve been thinking of it as an exo-Venus, with similar size and energy received from its star as our planetary neighbor in the solar system."
NASA has reported that the planet orbits a cool red dwarf star named Gliese 12. Compared to our sun, Gliese 12 is much smaller, approximately 27 per cent of the sun's size, and boasts about 60 per cent of its surface temperature.
Assuming the planet lacks an atmosphere, NASA astronomers estimate its surface temperature to be around 107 degrees Fahrenheit.
Red dwarf stars like Gliese 12 are particularly advantageous for discovering Earth-size planets due to their diminutive sizes and masses.
"A smaller star means greater dimming for each transit, and a lower mass means an orbiting planet can produce a greater wobble, known as 'reflex motion,' of the star," NASA said.
It added, "These effects make smaller planets easier to detect."
According to NASA, the reduced luminosity of red dwarf stars simplifies the task of assessing whether the planets orbiting them are potentially habitable and capable of hosting liquid water on their surfaces.
It said that the distance between Gliese 12 and Gliese 12 b is merely 7 per cent of the distance between Earth and the sun. Consequently, the planet receives approximately 1.6 times more energy from its star compared to Earth's solar radiation.
"Gliese 12 b represents one of the best targets to study whether Earth-size planets orbiting cool stars can retain their atmospheres, a crucial step to advance our understanding of habitability on planets across our galaxy," Shishir Dholakia, a doctoral student at the Centre for Astrophysics at the University of Southern Queensland in Australia, said in a statement.
Michael McElwain, a research astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said that the scientists need more such examples to understand the diversity of their atmospheres and their evolutionary outcomes.
"We know of only a handful of temperate planets similar to Earth that are both close enough to us and meet other criteria needed for this kind of study, called transmission spectroscopy, using current facilities," he said.
Screenshot of Gliese 12 b. Image Source: NASA official website
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