Alien life breakthrough on newly-discovered planet 'just like Earth'

Postado Novembro 15, 2017

Astronomers have discovered a planet 35 percent more massive than Earth in orbit around a red dwarf star just 11 light years from the Sun.

It was discovered by a team of researchers who are using the European Space Agency's High Accuracy Radial velocity Planet Searcher (HARPS) at the La Silla Observatory in Chile.

Lead author Dr Xavier Bonfils, of University Grenoble in France, said the planet orbiting a red dwarf star is the "closest known comfortable abode for possible life".

Ross 128 is now the second-closest planet that could be a potential candidate for life with Proxima B topping the list.

Scientists have suggested exoplanet Ross 128 b, which is only 11 light years away and roughly the same size as Earth, could potentially harbor alien life because it is temperate and its star is relatively calm. Vitally, the detection of biomarkers such as oxygen in the very closest exoplanet atmospheres will be a huge next step, which ESO's Extremely Large Telescope (ELT) is in prime position to take.

The closest one, known as Proxima b, may be less hospitable for life.

No other star system has ever been found to contain so many Earth-sized and rocky planets of the kind thought to be necessary to contain aliens. So why is Ross 128 b unique - apart from its rather human-sounding name?

Its temperature is estimated to lie between -60C and 20C, thanks to the cool and faint nature of its small red dwarf host star - which has just over half the surface temperature of the Sun.

"This discovery is based on more than a decade of HARPS intensive monitoring together with state-of-the-art data reduction and analysis techniques".

The findings of this research are slated to appear in the journal Astronomy & Astrophysics. Despite this proximity, Ross 128 b receives only 1.38 times more irradiation than the Earth. While the scientists involved in this discovery consider Ross 128b to be a temperate planet, uncertainty remains as to whether the planet lies inside, outside, or on the cusp of the habitable zone, where liquid water may exist on a planet's surface. Ross 128, the star in the constellation Virgo that this new exoplanet orbits, on the other hand, has been called inactive or quiet because it does not gush out similar amounts of radiation. Determining whether the planet is actually capable of supporting life as we know it, however, would require a better understanding of its atmosphere, Bonfils said. Close inspection reveals that Ross 128 has a unusual multiple appearance as this image was created from photographs taken over a more than forty year period by the Digitized Sky Survey 2, and the star, which is only 11 light-years from Earth, moved across the sky significantly during this time. 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.