NASA reported in a statement that has discovered an Earth-like planet 40 light years away that could be a promising candidate to host human life.
The exoplanet, called Gliese 12 bis slightly smaller than our planet and It has an estimated average surface temperature of 42 °C, assuming no atmosphere.
Gliese 12 b is located just inside the habitable zone, that is, at a distance from a star where there could be liquid water on the surface of orbiting planets.
Astronomers now plan to analyze Gliese 12 b to determine if it has an Earth-like atmosphere, which could reveal if the exoplanet can maintain the right temperature for water to form on its surface, the essential compound to support life.
Gliese 12 b has been classified as “the closest transiting, temperate, Earth-sized world to date”and is a candidate to be explored in the future by NASA’s James Webb Space Telescope.
The temperature of Gliese 12 b is between that of Earth and Venus
An international team of astronomers used the satellite TESS NASA’s Transiting Exoplanet Survey Satellite to pinpoint the location of Gliese 12 b.
The team discovered that Gliese 12 b has a much tighter orbit than Earthmeaning it crosses its cool red dwarf star, called Gliese 12, more often and completes one orbit every 12.8 days.
“Atmospheres trap heat and, depending on the type, can substantially change the actual surface temperature,” Dholakia explained. “We quote the ‘equilibrium temperature’ of the planet, which is the temperature it would have if it had no atmosphere”.
The team compared Gliese 12 b to Venus, and reported that it’s about the same size and receives slightly less energy from its star, around 85%.
Given the The temperature of Gliese 12 b is between that of Earth and Venusits atmosphere could teach us a lot about the habitability paths that planets take as they develop,” explained Larissa Palethorpe, a doctoral student at the University of Edinburgh and University College London.
Gliese 12 b represents one of the best targets to study whether Earth-sized planets orbiting cool stars can preserve their atmospheresa crucial step to advance our understanding of habitability on planets of our entire galaxy,” said Shishir Dholakia, a doctoral student at the Center for Astrophysics at the University of Southern Queensland in Australia.
The distance between the exoplanet and its dwarf star is only 7% of the distance between the Earth and the Sunwhich gives you 1.6 times more energy.
However, The habitability conditions of Gliese 12 b depend on it having the same type of atmosphere as Earthwhich makes its temperature closer to the average of 15 °C on our planet.
Gliese 12 shows no signs of storms
An important factor in understanding whether the exoplanet could be habitable is observe the level of storms emitted by its star.
Typically, red dwarf stars are magnetically active, making them project frequent X-ray flares that could destroy the atmosphere.
Some icy exoplanets could have oceans with liquid water and geysers
However, the teams have high hopes that this will not be the case, as the star Gliese 12 has not shown any signs of storms or extreme behavior.
To better understand the diversity of atmospheres and the evolutionary outcomes of these exoplanets, we need more examples like Gliese 12 b“said Michael McElwain, a research astrophysicist at NASA’s Goddard Space Flight Center and co-author of the Gliese 12 b study.
News reference:
https://svs.gsfc.nasa.gov/14581
