A recently discovered planet about 1,200 light-years away might be more habitable than Earth, according to scientists.
Researchers have devised a new index to help determine which exoplanets - any planet beyond our solar system - are most likely to be able to sustain life.
This information will be used when choosing which objects to focus our attention on as potentially habitable spaces.
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According to a paper published in the Astrophysical Journal, it pulls together a range of data, including 'transit data, stellar properties and previously reported limits on planetary emitted flux,' to do this.
This improves upon a previous method which relied heavily on the 'Goldilocks zone' or habitable zone - the range of orbits around a sun with the right temperature to support liquid water.
Going by the new and improved criteria, Earth has been assigned a habitability rating of 0.829.
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But, statistically there is a more habitable planet out there.
Kepler-442b, which was discovered by NASA's Kepler spacecraft between 2009 and 2012, orbits within the Goldilocks zone of the star Kepler-442 about 1,200 light-years away from Earth.
The exoplanet is described a super-Earth - its mass and radius are bigger than Earth's but smaller than Uranus and Neptune - and it has an equilibrium temperature of -40 degrees.
With a rating of 0.836, it is one of the more promising candidates for potential habitability.
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About the new measuring index, one of the paper's lead authors, Rory Barnes from the University of Washington’s Virtual Planetary Laboratory, said: "Basically, we've devised a way to take all the observational data that are available and develop a prioritisation scheme, so that as we move into a time when there are hundreds of targets available, we might be able to say, 'Okay, that's the one we want to start with'."
But, our search for Earth 2.0 may not be over just yet.
The actual habitability of Kepler-442b is uncertain because its atmosphere and surface are unknown.
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And, the Astrophysical Journal paper clarifies that just because a planet has a higher-than-Earth rating, it does not necessarily mean it is more suitable to sustain life than it.
In other space news, Mars has been declared unsafe for humans to live on.
After successfully landing robots on the red planet, NASA is continuing its plans to send humans up to join them.
But, it'll have to be a quick visit as researchers have found that exposure to radiation threats, including particle radiation from the Sun, distant stars, and galaxies, means no human could survive on the planet for more than four years.