Scientists Discover New Planet With Water

A handout artist's impression from ESA  Hubble shows the K2-18b super-Earth the only super Earth exoplanet known to host both water and temperatures that could support life

A handout artist's impression from ESA Hubble shows the K2-18b super-Earth the only super Earth exoplanet known to host both water and temperatures that could support life

Astronomers have detected water vapor in the atmosphere of a planet that orbits within the habitable zone of its star.

"From today onwards, we know K2-18b has atmosphere and water, making it the best known candidate for habitability", says Angelos Tsiaris, a UCL research associate in the Department of Physics and Astronomy and the lead author of the Nature paper.

"This study contributes to our understanding of habitable worlds beyond our Solar System and marks a new era in exoplanet research, crucial to ultimately placing the Earth, our only home, into the greater picture of the Cosmos", said Dr Tsiaras. None have been confirmed yet, however.

It's also closer to its star than the Earth is to the sun - so it has shorter years, because it completes its orbit in 33 days instead of 365.

Co-author Dr Ingo Waldmann (UCL CSED), said: "With so many new super-Earths expected to be found over the next couple of decades, it is likely that this is the first discovery of many potentially habitable planets".

"The fact we can now make observations that allow us to work out what's in the atmosphere of a planet twice the Earth's radius, orbiting a star that is just over a quadrillion kilometres away, is just fantastic".

The team, which posted its results yesterday on arXiv and has submitted them to The Astronomical Journal, also acquired data from NASA's Spitzer and Kepler space telescopes and fed them all into a climate model of K2-18b.

Tsiaras and his team think the planet is likely a rocky "super-Earth" in possession of an atmosphere that's either very water dominant, heavily mixed with a transparent gas like nitrogen, or features significant cloud formation. If the planet has an atmosphere, some wavelengths of light will be absorbed by the atoms or molecules in the atmosphere, leaving characteristic lines in the star's spectrum.

Professor Giovanna Tinetti said: 'Our discovery makes K2-18b one of the most interesting targets for future study'. Its star is relatively inactive, and hasn't put out any flares since scientists started observing the system.

NASA’s planet-hunting satellite TESS helps discover a'super-Earth and two gaseous sub Neptune-sized planets orbiting a nearby star 73 light years away

In a milestone for exoplanet research, two independent teams of astronomers have detected water vapor in the atmosphere of the planet K2-18b.

This image taken aboard the International Space Station, shows the limb of the Earth at the bottom transitioning into the orange-colored stratosphere, the lowest and most dense portion of the Earth's atmosphere.

The intriguing world, which goes by the impersonal designation K2-18b, lies 110 light-years away in the constellation Leo. Over time, the flow of charged particles and plasma from the sun stripped Mars' atmosphere away.

K2-18b will surely be receiving more attention from astronomers around the world, not only with existing telescopes but with next-generation ones, including NASA's James Webb Space Telescope, tentatively set for launch in 2021; and the European Space Agency's ARIEL space telescope, specifically created to study the atmosphere of exoplanets, and targeted for a 2028 launch.

"The Earth really stands out in our own Solar System".

Much remains unknown about the exoplanet K2-18 b, the researchers stressed. "To actually understand how habitability evolves in a hydrogen-rich atmosphere is going to be a very intense subject of study over the next 10 years".

Scientists analyzing the Hubble data say they found hydrogen and helium in K2-18's atmosphere as well. For now, there's no way to know what conditions on its surface are like. So, while the team knows there's water in the atmosphere, its abundance remains unknown.

However, the researchers behind another study - which was made available online Tuesday but has not been peer reviewed - told Space.com that the data indicates the presence of liquid water clouds that might produce rain on K2-18 b. While other, larger, gaseous planets - called hot Jupiters - have revealed some hints about the chemical elements contained in their atmospheres, this is the first time water vapour has been detected on a potentially habitable planet, an historic first.

More news: Next 007 should be a woman says Bond star Pierce Brosnan
More news: Tropical Storm Humberto increases odds of development as it heads toward Florida
More news: Galaxy Fold has 'hundreds of apps', including these top Android choices — Samsung

Recommended News

We are pleased to provide this opportunity to share information, experiences and observations about what's in the news.
Some of the comments may be reprinted elsewhere in the site or in the newspaper.
Thank you for taking the time to offer your thoughts.