Scientists Discover NEW Earth-Like Planet Within Habitable Zone Orbiting Proxima Centauri

Astronomers have discovered evidence for a new planet orbiting Proxima Centauri, the sun's nearest neighbour.

The alien planet is only one-tenth the size of Earth and orbits its parent star at one-tenth the distance between the sun and Mercury, the solar system's innermost planet.

Researchers discovered the new planet by examining minor wobbles in Proxima Centauri's velocity caused by the gravitational pull it exerts as it swings around the star. Observations with the European Southern Observatory's Very Large Telescope (VLT) in Chile indicate that the planet orbits the star once every five days.

The discovery demonstrates that our nearest stellar neighbour is "filled with exciting new worlds" that can be studied further and explored in the future, according to Joo Faria, a researcher at the Institute of Astrophysics and Space Sciences in Portugal and the study's primary author.

Scientists believe the planet orbits Proxima Centauri around 2.4 million miles (4 million kilometres), putting it closer to the star than its habitable zone, where the temperature range is just right for water to run freely. The findings have been published in the journal Astronomy & Astrophysics.

Named Proxima d, the planet is the third – and the lightest – to be spotted around Proxima Centauri, which at four light years away is the closest star to the solar system. It joins Proxima b, a planet with a mass comparable to that of Earth, which completes an orbit every 11 days, and Proxima c, which is believed to take about five years to circle the star.

The first hints of the planet came in 2020 when astronomers were observing Proxima Centauri to confirm the existence of Proxima b. The measurements revealed a weak signal in the star’s motion that had the hallmarks of being caused by a planet orbiting every five days.

Further observations taken with an instrument on ESO’s telescope called Espresso confirmed astronomers’ suspicions that a planet was the cause and not changes in the star itself.

“This is a very low mass planet, and is the third candidate around the star closest to us,” Faria said. “It shows that these planets, similar to the Earth, may be common in our galaxy, and just close by. And it makes us wonder about the possible conditions for habitability in these planet systems and if it’s possible for life to appear in other places in the universe.”

Reference(s): Astronomy & Astrophysics