Astronomers Find Water On Five Exoplanets, But Can They Support Life?

Scientists recently detected water in the atmospheres of five exoplanets – planets outside the solar system – broadening the search for life beyond our little blue rock. According to Space.com, the five planets, discovered in two sweeps by NASA's Hubble Space Telescope, orbit nearby stars and may contribute to our understanding of whether exoplanets could support life.

Astronomers have previously discovered evidence of water on several exoplanets, but new research identified individual atmospheres more accurately using measurements of infrared wavelength. The planets, known as “hot Jupiters,” are similar to Jupiter in size but much hotter because of their closer proximities to their respective stars.

"These studies, combined with other Hubble observations, are showing us that there are a surprisingly large number of systems for which the signal of water is either attenuated or completely absent," Heather Knutson of the California Institute of Technology in Pasadena, a co-author on one of the studies, said in a statement. "This suggests that cloudy or hazy atmospheres may in fact be rather common for hot Jupiters."

The studies are part of an inventory of exoplanet atmospheres. The census is led by L. Drake Deming of the University of Maryland in College Park.

Using Hubbles’ Wide Field Camera 3, astronomers were able to detect water signatures on five planets trillions of miles away by looking at how their atmospheres absorbed light. Comparing absorption profiles, including their shapes and intensities, allowed them to pinpoint on which expolanets water was present. Astronomers can figure out what gases are present inside a distant planet’s atmosphere by determining which wavelengths of the nearby star’s light are absorbed and which are transmitted.

Unfortunately, just because there’s water on a planet, doesn’t mean life as we know it can survive there. According to Space.com, because the planets’ surface temperatures are so hot, they are unlikely to support life.

Still, the research helps astronomers narrow down candidates where life could potentially exist beyond our solar system.

"We're very confident that we see a water signature for multiple planets," Avi Mandell, of NASA's Goddard Space Flight Center in Greenbelt, Md., lead author of one of the studies, said in a statement. "This work really opens the door for comparing how much water is present in atmospheres on different kinds of exoplanets — for example, hotter versus cooler ones."