London, July 12 (ANI): A new research has suggested that hot and massive, rocky worlds called 'super-Earths', may provide the right conditions for life, even those orbiting searingly close to their stars.
According to a report in New Scientist, at up to 15 times the mass of Earth, the rocky bodies are bigger and easier to spot than Earth-sized worlds, which have yet to be detected.
In fact, technological advances recently led to the discovery of up to 45 new super-Earths, and astronomers say a third of all Sun-like stars may host the brawny planets.
As to the question if such planets can host life or not, Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics in Massachusetts, US, said, "There's no reason why the different chemical cycles that are important for life on our planet wouldn't work on super-Earths."
Super-Earths orbiting close to their stars experience gravitational tugs that keep them 'tidally locked' to their hosts.
That means one side of such a planet always faces its star, the way the Moon always shows the same side to Earth.
Astronomers previously assumed such planets would be two-faced worlds of fire and ice, with one half molten and the other frozen.
Early models suggested the atmospheres of such worlds would quickly vanish, as water vapour and other atmospheric molecules on the planet's dark side would turn to ice and plunge to the ground.
"It was thought that after the atmosphere on the dark side was completely iced out, then it would suck atmosphere from the hot side, freezing that out as well," Kaltenegger told New Scientist.
But new models show that if a tidally locked super-Earth has an atmosphere at least as dense as Earth's, strong winds could transport heat from its hot side to its cold side. Similarly, if the planet has a global ocean, its currents could help spread the warmth.
This effect still wouldn't offset the intense heat the planets would experience at close distances to Sun-like stars.
But it means that super-Earths could potentially host life as close as 0.05 astronomical units away from dim stars known as red dwarfs, which make up about 85% of the stars in the galaxy.
According to scientists, in some ways, super-Earths might even be more likely to support life than their Earth-sized cousins.
Recent research suggests that super-Earths will experience more plate tectonic activity than smaller rocky worlds.
It plays a crucial role in the carbon-silicate cycle, which releases carbon dioxide into the atmosphere, warming the planet.
According to Diana Valencia, a graduate student at Harvard, "If we're concerned about finding life, those are the planets we should be investigating right now." (ANI)
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