NASA says another Earth-sized planet has been discovered 'in habitable zone'

This planet, which lies only 11 light-years from Earth, was found by a team using ESO's unique planet-hunting HARPS instrument.

Ross 128b has a few things going for it that make it a much better candidate to support human life.

European scientists found Ross 128 b using HARPS, the High Accuracy Radial velocity Planet Searcher.

Scientists still aren't quite sure what the planet's surface looks like, or whether there is liquid water present. However, Ross 128 is a particularly calm and cool dwarf star, only about 20 percent the diameter of the sun with a little more than half the sun's surface temperature.

Despite its proximity to its star, Ross 128 b only absorbs about 1.38 times as much radiation as our planet, giving the Earth-sized world a hospitable equilibrium temperature in the range of -60 to 20 °C (-76 to 68 °F). Orbiting planets, while tiny, can gravitationally tug on a star, causing the star to shake in its orbit. The ESO's Extremely Large Telescope could find out whether Ross 128 b possesses oxygen or other chemical markers that could be signs of habitability or extant life. You see Ross 128 is actually moving towards our solar system at tremendous speed which means that in around 79,000 years it will actually overtake Proxima B to become our closest exoplanet with an Earth-like temperature.

Another tantalizing planet has been found outside our Solar System: an Earth-sized world that's our cosmic next-door neighbor - and it could be in just the right spot to host life. Unlike Proxima Centauri, Ross 128 is said to be "quiet", meaning it spews out comparatively less radiation that could harm life as we know it.

Nearby exoplanet is a target for life

"Only HARPS has demonstrated such a precision and it remains the best planet hunter of its kind, 15 years after it began operations", explains Nicola Astudillo-Defru (Geneva Observatory - University of Geneva, Switzerland), who co-authored the discovery paper.

The question "are we alone in the universe?" has bewildered mankind for eons as the search for alien life thus far has yielded no results. Considering the oldest human remains are thought to be hundreds of thousands or even millions of years old, it's not insane to think our species could still be roaming the Earth when Ross 128 b becomes the closest exoplanet to our home world. Earlier this year, Ross 128 made headlines because it appeared to be sending out a semi-repeating radio signal.

While the scientists involved in this discovery consider Ross 128b to be a moderately temperate planet, uncertainty persists as to whether the planet is inside, outside, or at the top of a habitable zone, where liquid water exists on the surface of the planet. Maybe we'll have them by the time the planet gets closer.

Though both Ross 128 and Proxima Centauri are red dwarfs - the most common type of star in the Milky Way galaxy - they are very different objects.

Earlier this year, scientists said that they had received odd pulses coming from the star.

  • Gwendolyn Kim