They detect water in the atmosphere of a potentially habitable “super earth”

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(CNN) - For the first time, astronomers have observed the atmosphere of an exoplanet, a planet outside our solar system, and have discovered both water vapor and temperatures that could support life, according to a new study.

The exoplanet, known as K2-18b, is eight times the mass of the Earth and is known as a super earth, or exoplanets between the mass of the Earth and Neptune. It orbits a red dwarf star 110 light years from Earth in the constellation Leo. The planet was first discovered in 2015 by NASA's Kepler spacecraft.

A research team used archived data collected by the Hubble Space Telescope between 2016 and 2017 that captured the light of the stars as they passed through the exoplanet's atmosphere. The researchers said they clearly saw the signature of water vapor in the atmosphere when they put the data through algorithms. They also observed the signatures of hydrogen and helium in the atmosphere, two of the most abundant elements in the universe.

The detection of water vapor in the atmosphere of this exoplanet is particularly exciting for researchers because the exoplanet is also within the habitable zone of its star, which includes the correct temperatures for liquid water on the planet's surface and that It can possibly house life as we understand it.

The researchers published their findings in the journal Nature Astronomy on Wednesday.

"Finding water in a potentially habitable world other than Earth is incredibly exciting," said Angelos Tsiaras, author of the study and associate researcher at the Space Exochemistry Data Center at University College London. “K2-18b is not the 'Earth 2.0' since it is significantly heavier and has a different atmospheric composition. However, it brings us closer to answering the fundamental question: Is the Earth unique?

READ : Astronomers capture two growing exoplanets in a photograph

The exoplanet completes an orbit around its star every 33 days and is much closer to its star than the Earth of the Sun. But the red dwarf star is also much colder than our Sun. According to researchers' calculations, they believe that the planet could even be at a temperature similar to Earth's. But the range is extended to include much colder or warmer temperatures than Earth due to the limitations of its data.

The red dwarf star is active, however, which makes it likely to expose the exoplanet to more radiation than Earth receives.

"With so many new super-earths expected to be found in the next two decades, this is likely to be the first discovery of many potentially habitable planets," said Ingo Waldmann, co-author of the study and professor of extrasolar planets at the Space Exochemistry Data Center from University College London. "This is not only because super-earths like K2-18b are the most common planets in our galaxy, but also because red dwarfs - stars smaller than our Sun - are the most common stars."

The Hubble Space Telescope is only sensitive to water signature, but future telescopes such as the James Webb Space Telescope and the European Space Agency's ARIEL mission will be able to study exoplanet atmospheres in greater detail with more advanced instruments.

LOOK : The story of the Hubble telescope, NASA's eyes in space

The researchers believe that other elements such as nitrogen and methane may also be present in the atmosphere, but only future observations of more advanced telescopes will reveal them.

"Our discovery makes K2-18b one of the most interesting goals for future studies," said Giovanna Tinetti, co-author of the study and principal investigator for ARIEL. “More than 4,000 exoplanets have been detected, but we don't know much about their composition and nature. By observing a large sample of planets, we hope to reveal secrets about their chemistry, formation and evolution. ”

Exoplanet