Astronomers reveal top 20 planets with aliens, most similar to Earth

7 years ago

Astronomers reveal top 20 planets with aliens, most similar to Earth

The United States Aeronautic Space Agency (NASA’s) Kepler telescope has been busy in the hunt for alien life, finding over 4,000 new planets outside Earth’s solar system over the past three years.

Now a team of astronomers has narrowed down this list to those with the most potential to have liquid water, or even life.They pinpointed 20 out of the 4,000 that are most likely to be like our own, and are starting to look more closely at these candidates.The ‘habitable zone’ is an area around a star in which an orbiting planet’s surface could hold liquid water.

The boundaries of the habitable zone are critical. If a planet is too close to its star, it will experience a runaway greenhouse gas effect, like Venus. But if it’s too far, any water will freeze, as is seen on Mars.A group led by San Francisco State University physicists searched through the list Kepler had returned to find those most likely to support life like our own.

They found 216 Kepler planets are located within the ‘habitable zone’ – an area around a star in which an orbiting planet’s surface could hold liquid water.Of those, they list 20 that are the best candidates to be habitable rocky planets like Earth.These include Kepler-186 f, Kepler-62 f, Kepler-283 c and Kepler-296 f.
Meanwhile, if reports of a new discovery are to be believed, of all the 100 billion stars in our universe, the one closest to us might just be one that supports alien life.According to reports, a newly-spotted planet in our galactic neighbourhood might have the right conditions for life.

Scientists spotted the planet, which is believed to be ‘Earth-like’, orbiting the star Proxima Centauri, the nearest stellar neighbour to our sun.The researchers are due to unveil the discovery later this month and apparently believe it orbits its star at a distance that could favour life – the so-called habitable zone, claims German weekly Der Spiegel.

Proxima Centauri is part of the Alpha Centauri star system just 4.2 light years from our own solar system.According to Der Spiegel, the European Southern Observatory (ESO) will announce the finding at the end of August.ESO spokesman Richard Hook said he is aware of the report, but refused to confirm or deny it. “We are not making any comment,” he said.

Proxima Centauri is the closest star to our own. A planet orbiting the star would be the closest exoplanet to Earth.Discovered in 1915, Proxima Centauri is one of three stars in the Alpha Centauri system, a constellation mainly visible from the southern hemisphere.The planet is thought to be in the star’s ‘habitable zone’ – an area around a star in which an orbiting planet’s surface could hold liquid water.

Meanwhile, a new theory has claimed if conditions had been just a little different, life could exist on a lush, green Venus and Earth would be a dead planet.Researchers say that minor evolutionary changes could have altered the fates of both Earth and Venus – and hope to soon be able to model them.

This could make the search for alien life far more fruitful, and rewrite the theory of ‘goldilocks zones’ where life can exist. The hypothesis by Rice University scientists and their colleagues is published in Astrobiology this month.

The Goldilocks zone has long been defined as the band of space around a star that is not too warm, not too cold, rocky and with the right conditions for maintaining surface water and a breathable atmosphere.

But that description, which to date scientists have only been able to calibrate using observations from our own solar system, may be too limiting, Rice Earth scientist Adrian Lenardic said.Lenardic and his colleagues suggested that habitable planets may lie outside the ‘Goldilocks zone’ in extra-solar systems, and that planets farther from or closer to their suns than Earth may harbor the conditions necessary for life.