MADRID, Aug 2 – An international team of astronomers has discovered a new habitable solar system with a planet that can be inhabited, a Spanish astrophysicist who is leading the research said yesterday.
Three new planets have been discovered in orbit GJ 357, a red dwarf – a small and cooling star of 31 light years, relatively close in space, said Rafael Luque of the Spanish Institute of Astrophysics in the Canary Islands.
The discovery was also reported by Nasa, whose TESS planet hunting satellite made this possible.
The planet known as GJ 357d – farthest from the star – was particularly intriguing, as researchers believe it could be habitable. The other two are considered too hot.
Signs of habitation on each planet include rocky terrain with a magnitude similar to Earth and distance from the sun – the temperate zone of the Goldfish neither too close nor too far – allowing the right temperature of liquid water, a key requirement for life,
Given its distance from a star similar to Mars to our Sun, researchers believe the planet has temperatures of -53 degrees Celsius, Luque told AFP.
"That looks a little cold," he said.
But "if this planet had an atmosphere (unlike Mars), it could hold the heat it receives from its star and the water could be liquid."
According to the researchers, the GJ 357d could be about the same size as Earth or up to twice its size.
This is not the first potentially habitable planet found near us.
In 2016, the discovery of Proxima b just four light-years away from the solar system made waves.
But there is a stop.
Proxima b and GJ 357d were detected by a so-called radial velocity, which involves the search for signs of oscillation in a star by a gravitational tug on an orbiting planet.
But Luke says the method is not accurate enough to determine if it is actually habitable.
As things stand, to measure its size, density and composition, the planet must pass directly between its star and observer, the so-called "transit" method, he says.
That was not possible for Proxima b and other nearby potentially habitable planets, Luque says.
In the coming months, Luke and his team will work to try and catch the GJ 357d on "transit" to try and confirm it as a habitable planet.
"The likelihood of a planet passing a star from our line of sight on Earth is quite small," he adds. – AFP