The National Aeronautics and Space Administration has announced its discovery of not just one but seven Earth-sized planets have been found orbiting the habitable or ‘temperate zone’ of a star.
The newly-discovered heavenly bodies were just 39 light-years away from our mother Earth.
According to the research findings, at least the inner six planets appear to have Earth-like masses, are made of rock, and have surface temperatures ranging between a life-friendly 0 to 100°C (32 to 212°F).
The NASA named it as a ‘sister solar system’ to our own, and says several of the planets could potentially host liquid water, and maybe even extraterrestrial life.
The space agency announced the discovery following a triggering much speculation over their big “discovery beyond our Solar System”.
The new exoplanets have been detected orbiting an ultracool dwarf star called TRAPPIST-1, which is located about 39 light-years away from our Sun in the Aquarius constellation.
Utilizing Earth-based telescopes, Astronomers led by Michaël Gillon from the University of Liège in Belgium first detected three exoplanets around the star back in May 2016.
The research team also used NASA’s Spitzer space telescope that they discovered an additional four planets in the system.
Based on their initial estimates that at least five of the planets have masses similar to Earth, and follow-up observations by the Hubble Space Telescope indicate that they probably have rocky compositions.
At least three also appear to fall within the temperate zone of their star – which means their surface temperatures are most likely to be between 0 and 100°C (32 and 212°F), making liquid water, and potentially even some form of extraterrestrial life, a possibility.
With the glimpse of the said the system’s structure, experts believed that it also possible that any of the planets have liquid water.
Meanwhile, the European Space Observatory is calling it “the most incredible star system to date“.
The full findings were published in Nature.
“The TRAPPIST-1 system is a compact analogue of the inner Solar System,” the authors write in Nature.
“In the past few years, evidence has been mounting that Earth-sized planets are abundant in the Galaxy, but Gillon and collaborators’ findings indicate that these planets are even more common than previously thought,” Ignas A. G. Snellen, an astronomer from the Leiden University in the Netherlands who wasn’t involved in the research, writes in an accompanying opinion piece in Nature.
He explains the significance in more detail:
“From geometric arguments, we expect that for every transiting planet found, there should be a multitude of similar planets (20 to 100 times more) that, seen from Earth, never pass in front of their host star.
Of course, the authors could have been lucky, but finding seven transiting Earth-sized planets in such a small sample suggests that the Solar System with its four (sub-)Earth-sized planets might be nothing out of the ordinary.”