Scientists discover ‘super-Earth’ planet that may be suitable for life
The exoplanet, which has been named HD 20794 d, orbits in the ‘habitable zone’ of a nearby star similar to our sun.
Scientists have discovered a “super-Earth” planet that may have conditions suitable for life, according to the University of Oxford.
The exoplanet – a planet outside our solar system – has a mass six times greater than that of Earth, and orbits in the “habitable zone” of a nearby star similar to our sun 20 light-years away from our solar system.
Orbiting in the zone means the planet, named HD 20794 d, is at the right distance from the star to sustain water on its surface, but because this distance changes over the course of its elliptical rather than circular orbit it is too early to say whether it could host life.
Dr Michael Cretignier, a postdoctoral research assistant in the Department of Physics at the University of Oxford, first identified a possible signal for the exoplanet in 2022 while analysing archived data recorded by the High Accuracy Radial Velocity Planet Searcher spectrograph at the La Silla Observatory in Chile.
An international team of researchers went on to analyse two decades of observations to confirm the discovery.
“We worked on data analysis for years, gradually analysing and eliminating all possible sources of contamination,” Dr Cretignier said.
“For me, it was naturally a huge joy when we could confirm the planet’s existence.
“It was also a relief, since the original signal was at the edge of the spectrograph’s detection limit, so it was hard to be completely convinced at that time if the signal was real or not.
“Excitingly, its proximity with us (only 20 light-years) means there is hope for future space missions to obtain an image of it.”
Researchers hailed the planet as an “invaluable test case” for space projects looking to detect signs of life outside our solar system.
“With its location in a habitable zone and relatively close proximity to Earth, this planet could play a pivotal role in future missions that will characterise the atmospheres of exoplanets to search for biosignatures indicating potential life,” Dr Cretignier said.
“While my job mainly consists of finding these unknown worlds, I’m now very enthusiastic to hear what other scientists can tell us about this newly discovered planet, particularly since it is among the closest Earth-analogues we know about and given its peculiar orbit.”
The findings have been published in the journal Astronomy & Astrophysics.
