ESA

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Waterworld: up to 50% from the atmosphere of the K2-18b can have out of the water

astronomers have for the First Time discovered water in the atmosphere of a planet's Orbit within the habitable zone of a Distant Star .

The finding makes The World , that is, K2-18b - a plausible candidate for The Search for extraterrestrial life.

Within 10 years, New Space telescopes might be able to determine whether or not K2-18b atmosphere contains gases that could be produced from living organisms.

the Details were published in the journal.

The Lead scientist, Prof Giovanna Tinetti from University College London (UCL), described The Discovery as "mind blowing".

"this is The First Time that we have found water on a planet in the habitable zone around a star in which the temperature is potentially compatible with The Presence of life," She Said .

The habitable zone is the region around a star where temperatures are considered to be sufficiently benign so that the water exist in liquid form on The Surface of a planet.

The new planet is only about twice the size of Earth in a planet of the type known as a "super-Earth " and has a temperature cool enough to have liquid water, between zero and 40C.

K2-18b is 111 light-years - about 650 million million miles from Earth , too far to send a sample. So the only option is to wait for the next generation of space telescopes will be launched that could be made in the 2020s, and are looking for gases in the atmosphere of The Planet just by living organisms.

What an exoplanet is?

The Team behind The Discovery looked through the planets discovered with the Hubble space telescope between 2016 and 2017. The researchers have identified some of the chemicals circled in your atmosphere by examining the changes in the starlight as the planets to their suns. The Light , filtered through The Planet 's atmosphere was subtle, the composition of the atmosphere changed.

Only K2-18b showed the molecular signature of water is a key ingredient For Life on Earth .

Dr. Angelos Tsiaras, member of the UCL team, said that The Search for water was in the atmosphere a "potentially habitable exoplanets incredibly exciting".

Other astronomers, however, the assertion that the Earth may be habitable. An analysis shows that the planets, are the 1. 5 times the mass of Earth are unlikely to have a rocky surface. There is also the concern that K2-18b size and gravity would make it difficult for The World to support life.

Other critics instead suggest that The Planet Earth should be considered as a super -, but also as a mini-Neptune. This is a class of planets that, in General, more massive than a super-Earth (it contains worlds up to 10 times the mass of Our Own planet). Prof Tinetti, however, maintains its view that the New World is potentially habitable.

She Said it had an average density comparable to that of Mars (the silicates) and the Jupiter Moon Europa, and much higher than that of Neptune.

"K2-18b cannot be classified as a mini-Neptune, rather, it is a planet with an interior of rock and ices. These types of planet, [are] sometimes referred to as "ocean-planet"," she told Bbc News .

"Well, if this planet is really a ocean on The Surface or rock, we can't say with current observations, but the water in the atmosphere is a good place to start. "

But there is a view that Dr. Laura Kreidberg, of the center for astrophysics at Harvard University , does not agree.

"The Interior of The Planet is much more like Neptune. Pressure and temperature increase with depth, so that a rocky surface is achieved, it is too hot to form high pressure in the case of complex molecules such as DNA or any of The Other building blocks of life," she told Bbc News .

Prof David Anthony Hibbert, also of Harvard University , said the fact that the K2-18b atmosphere was detected, was a proof in itself that it will not support life.

"If The Planet had a thin secondary atmosphere similar to Earth it would be so thin that the Hubble telescope couldn't see it. "

Esa Ariel's mission is to help in 2028 could confirm The Presence of life on other worlds long-range

Another Problem is that astronomers do not agree on what conditions are necessary for habitability. We have only the Earth , but life can also be possible on other types of worlds

It is likely to be a study of the chemical composition of perhaps hundreds of worlds and an understanding of how they arise and develop, require, according to Prof Tinetti.

"The Earth is really in Our Own Solar System . There is oxygen, water and ozone. But when we find, that all, said to be a planet around a Distant Star , we must say to be careful that it supports life," She Said .

"That is why we need to understand, not only a handful of planets in The Galaxy , but hundreds of them. And, what we hope, is that the habitable planet stand out is that we will see a Big Difference between the planets that are habitable and which are not. "

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Source of news: bbc.com