NASA’s Hubble Telescope disappointingly found three exoplanets that revolve around stars similar to the sun have low levels of water vapor in their atmospheres.
For years, NASA has been using its Hubble Telescope to search for exoplanets that contain water vapor in their atmospheres, as it could indicate life. The space agency thought it found ideal candidates in HD 189733b, HD 209458b, and WASP-12b, three planets that move around stars that are highly similar to the sun.
The planets, which are between 60 and 900 light-years away, have temperatures between 900 to 2200 degrees Celsius. And, unfortunately, the Hubble Telescope found that they have almost completely dry atmospheres, which means they are almost definitely not supporting life.
Scientists had predicted much more water on the planets, making these discoveries very disappointing.
“Our water measurement in one of the planets, HD 209458b, is the highest-precision measurement of any chemical compound in a planet outside the solar system, and we can now say with much greater certainty than ever before that we’ve found water in an exoplanet,” said Dr Nikku Madhusudhan of the Institute of Astronomy at the University of Cambridge. “However, the low water abundance we are finding is quite astonishing.”
The scientists then explained how this will impact the way they will view planets similar to Earth, at least from a life-sustaining standpoint.
“It basically opens a whole can of worms in planet formation. We expected all these planets to have lots of water in them. We have to revisit planet formation and migration models of giant planets, especially ‘hot Jupiters,’ and investigate how they’re formed,” Madhusudhan said. “We should be prepared for much lower water abundances than predicted when looking at super-Earths (rocky planets that are several times the mass of Earth).”
Although these three exoplanets turned out to not have any water, NASA researchers and other scientists will still be searching for more life-sustaining planets in the future. Only this time, they will have more of an idea of what to look for.
“There are so many things we still don’t understand about exo-planets; this opens up a new chapter in understanding how planets and solar systems form,” Madhusudhan concluded.
The findings were published in in The Astrophysical Journal Letters.