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There are two distant planets probably made of waterAccording to a study using NASA’s Hubble and Spitzer telescopes.
“Water worlds” orbit a red dwarf star, the smallest and coolest star. This is stated in the information of NASA’s Jet Propulsion Laboratory.
NASA says the watery planets are 218 light-years away in the constellation Lyra. They are “unlike any planet found in our solar system,” the agency says.
The discovery that the planets are likely to consist of water comes from it A study published in the journal Nature Astronomy Thursday. A research team led by Caroline Piaulet, a doctoral student at the University of Montreal’s Institute for Exoplanet Research, observed the distant planetary system using NASA’s Hubble and Spitzer space telescopes.
The planetary system they studied is called Kepler-138 because it is within the field of view of NASA’s Kepler spacecraft. Although researchers are aware of the existence of three exoplanets within the Kepler-138 system – the term for planets outside our solar system – they have discovered that only two of them contain water.
They also discovered evidence for a previously undescribed fourth planet.
But the finding is not as simple as it seems. Scientists have not directly detected water on Kepler-138c and Kepler-138d exoplanets. Instead, they compared the sizes and masses of the planets to the models for comparison.
Comparing the planets to models, they found that “a significant fraction of their volume—up to half—must be made of materials lighter than rock but heavier than hydrogen or helium.”
Water is the most likely candidate for material that is lighter than rock but heavier than hydrogen or helium, NASA says.
“We used to think that planets slightly larger than Earth were large spheres of metal and rock, like enlarged versions of Earth, so we called them super-Earths,” said study co-author Björn Benneke. emeritus professor of astrophysics at the University of Montreal. “However, we have now shown that these two planets, Kepler-138c and d, are quite different in nature and are likely to contain a large proportion of their entire volume of water.”
“This is the best evidence yet for water worlds, a type of planet that has long been theorized by astronomers to exist,” Benneke said.
According to NASA, the high temperatures on these planets indicate that they may be surrounded by vaporous atmospheres.
“The temperature in Kepler-138d’s atmosphere is probably above the boiling point of water, and we expect a thick, dense atmosphere of vapor on this planet,” Piaulet said in the release. “Only under this vapor atmosphere can there potentially be liquid water at high pressure, or water in another phase that occurs at high pressure, called a supercritical fluid.”
“Water worlds” are outside their star’s habitable zone—the region where temperatures allow liquid water to exist on the surface of a rocky planet, potentially supporting life. But the new planet described by the researchers, Kepler 138e, falls in that right zone, according to the release.
