Alright, who wants to go?
Alright folks, Australian astronomers have discovered the closest ever habitable planet outside of our solar system — just 14 light years away, or 126 trillion kilometers. Now you may be thinking, 126 trillion kilometers is pretty far, but if you consider that our closest planetary neighbor Mars is between 54.6 and 401 million kilometers away from Earth, trillions of kilometers actually sounds doable.
The planet, named Wolf 1061c, is 4.3 times the mass of Earth, and is one of three planets orbiting around a red dwarf ‘M-type’ star called Wolf 1061. “It is a particularly exciting find because all three planets are of low enough mass to be potentially rocky and have a solid surface, and the middle planet, Wolf 1061c, sits within the ‘Goldilocks’ zone where it might be possible for liquid water — and maybe even life — to exist,” said lead author of the study, Dr. Duncan Wright from the University of New South Wales (UNSW).
Wolf 1061c orbits the relatively cool and stable star every 18 days at a distance approximately 10 percent Earth’s orbit of the sun. In our solar system that would spell immediate doom, however since the star is so cool (3,300 Kelvin compared to our Sun at 5,800 Kelvin), the potential for life is there, and astronomers are thrilled. “This discovery is especially exciting because the star is extremely calm," Wright told Stuart Gary of ABC News. "Most red dwarfs are very active, giving out X-ray bursts and super flares, which spells doom for any life, given the habitable zone is so close into these stars.”
Wright also added that the proximity of Wolf 1061c to its sun indicates that it is likely “tidally locked” — meaning one side will always be facing the star. “This changes the circumstances on the surface of the planet substantially,” he told Marcus Strom at The Sydney Morning Herald. “You have one very hot side and one very cool side.”
The team made the discovery analyzing more than a decade’s worth of observations of Wolf 1061 collected by the High Accuracy Radial Velocity Planet Searcher (HARPS) spectrograph, located on the European Southern Observatory’s 3.6 meter telescope in La Silla, Chile. They applied the “doppler wobble method” to identify the planets, which picks up on signal changes due to smaller objects like planets orbiting larger objects like stars.
“The close proximity of the planets around Wolf 1061 means there is a good chance these planets may pass across the face of the star. If they do, then it may be possible to study the atmospheres of these planets in the future to see whether they would be conducive to life,” explained team member UNSW's Dr. Rob Wittenmyer.
The discovery of rocky planets that resemble Earth is nothing new — they are actually quite abundant in our galaxy. However, most of these exoplanets have been discovered hundreds and even thousands of light years away.
“It is fascinating to look out at the vastness of space and think a star so very close to us — a near neighbour — could host a habitable planet,” said Wright.
Almost like it was right under our noses.
Ever wonder how scientists find these "Earth-like" planets? Read The Hunt is On: How Scientists Look For Alien Life
*Editor's Note (January 4): The original article compared the distance to Wolf 1061c with the average distance to Mars. For clarity, this has been changed to the minimum and maximum distance to Mars.