The water world was discovered using the Hubble and Spitzer telescopes.
REPUBLIC.CO.ID, JAKARTA – Scientists are observing exoplanets with the United States Aeronautics and Space Administration’s Hubble Space Telescope and the retired Spitzer Space Telescope. They discovered that planets are mostly composed of water. The planets are Kepler-138c and Kepler-138d.
These two planets, and a smaller companion planet closer to their star (Kepler-138 b), were previously discovered by NASA’s Kepler Telescope. The new study also found evidence of a fourth planet.
How to detect water in Kepler-138c and Kepler-138d?
Reported by Space, water has not been directly detected in Kepler-138 c and d. Scientists know this by comparing the sizes and masses of planets with models.
Astronomers concluded that most of its volume (even half) must be made of a material lighter than rock but larger than hydrogen or helium (which make up most of gas giant planets like Jupiter). The most common candidate material is water.
It is commonly known that in this world there are rocky planets, there are gas giant planets. There are also theories about the water world. These properties are usually known from a comparison of the mass and size of the planet.
“We previously thought that planets slightly larger than Earth were large spheres of metal and rock, like enlarged versions of Earth, which is why we called them super-Earths,” explained Björn Benneke, study co-author and professor of astrophysics at the University of Montreal (12/16/2022).
