CNN
—
Two planets far apart probably made of wateraccording to research conducted using NASA’s Hubble and Spitzer telescopes.
The so-called “water world” orbits the smallest and coldest kind of star, the red dwarf. According to a news release from NASA’s Jet Propulsion Laboratory.
The water planet is 218 light-years away in the constellation Lyra, NASA says. And they are “different from any planets found in our solar system,” the agency said.
The discovery that the planet is likely to be composed mostly of water Research published in Nature Astronomy on thursday. A research team led by Caroline Piolet, a PhD student at the University of Montreal’s Institute for Exoplanets, used NASA’s Hubble and Spitzer Space Telescopes to observe distant planetary systems.
The planetary system they studied is called Kepler-138 because it is within the field of view of NASA’s Kepler spacecraft. Researchers knew that there are three exoplanets (a term used to describe planets outside the solar system) in the Kepler-138 system, but two of them were likely made of water. I discovered it only recently.
They also found evidence of a previously undescribed fourth planet.
But discovery is not as simple as it seems. Scientists have not directly detected water on the exoplanets Kepler-138c and Kepler-138d. Instead, they compared the size and mass of the planets against models.
Comparing the planet to models, they found that “a significant fraction of its volume, up to half, should be made of matter lighter than rock and heavier than hydrogen and helium.”
According to NASA, water is the most likely candidate for a substance that is lighter than rock and heavier than hydrogen and helium.
“Previously, planets slightly larger than Earth were thought to be large spheres of metal and rock, similar to an enlarged version of Earth. That’s why we called them super-Earths.” and the co-author of the study, Professor of Astrophysics at the University of Montreal. “However, these two planets of his, Kepler-138c and d, are quite different in nature, indicating that most of their overall volume is likely to be composed of water.”
“This is the best evidence yet for a water world, the type of planet long theorized by astronomers to exist,” Beneke continued.
According to NASA, the high temperatures of these planets mean they may be enveloped in vaporous atmospheres.
“The temperature of Kepler-138d’s atmosphere is likely above the boiling point of water, and the planet is expected to have a thick, dense atmosphere of steam,” Piaulet said in a release. “Only under that vaporous atmosphere can there be high-pressure liquid water, or even another phase of water that occurs at high pressures called supercritical fluids.”
“Water worlds” lie outside the stellar habitable zone (the temperature at which liquid water exists on the surface of rocky planets and can sustain life). But Kepler 138-e, a new planet described by researchers, falls into just that right zone, according to the release.
