Astronomers have identified 45 planets that could be the best places to search for alien life.
Scientists have found more than 6,000 exoplanets, or worlds outside of our own solar system.
But many of them are inhospitable to any kind of life, because they are too hot, cold or otherwise dangerous.
Now astronomers have suggested 45 of them that could support life, including famous examples such as Proxima Centauri b, TRAPPIST-1f and Kepler 186f, according to The Independent.
Researchers suggest that the list could be a starting point when looking for signals that could indicate alien life – or potentially sending a spacecraft.
The planets could also help us identify whether our current framework for deciding whether a life could support life, known as the habitable or goldilocks zone, works as a good way of choosing which planets to study by looking at those on the edge of the habitable zone.
The most exciting of the worlds on the list are in the Trappist-1 system, based around a star about 40 light years away. They and some other planets top the list for getting light in a similar way to the Sun on Earth.
But much will depend on whether those worlds have an atmosphere that would actually allow them to hold water, which is thought to be key to life.
“While it's hard to say what makes something more likely to have life, identifying where to look is the first key step – so the goal of our project was to say 'here are the best targets for observation',” said Gillis Lowry, a graduate student who worked on the study.
The researchers hope that the list can be used to help guide the observations of telescopes and spacecraft such as the James Webb Space Telescope, as well as the upcoming Nancy Grace Roman Space Telescope, Extremely Large Telescope, Habitable Worlds Observatory and others that might follow.
Those observations should help confirm whether the planets have atmospheres – the next test for whether they are really habitable.
The work is reported in a new paper, ‘Probing the limits of habitability: a catalogue of rocky exoplanets in the habitable zone,’ published in the journal Monthly Notices of the Royal Astronomical Society.