An Earth-sized planet with active volcanic activity and possibly an atmosphere has been discovered around a star about 90 light years away from Earth. At a distance of about 90 light years, it is relatively close to Earth for a planet outside the solar system, and it is possible to observe the composition of its atmosphere. A planet’s atmosphere is one of the important elements when investigating the origin of life, and the discovered planet attracts attention as an important research topic in the future.
This discovery was the result of an international research team at the University of Montreal in Canada and the University of Tokyo, and was published in the British scientific journal Nature. The observation target is in the direction of the constellation Crater, which is close to the name Hydra, and a planet the size of the Earth was discovered through observations with the Spitzer Space Telescope of the United States.
Further investigation using ground-based telescopes revealed that the orbit is slightly elliptical due to the influence of another planet orbiting outside the Earth-sized planet. In its distorted orbit, the planet deforms very slightly as the gravitational influence of the central star waxes and wanes. At this time, it was concluded that there was a high possibility that friction was occurring inside the planet and heating it, causing active volcanic activity on the surface. In the solar system, a similar mechanism works on Jupiter’s moon Io, which is known to have volcanic activity and a thin atmosphere.
The outer planet of this Earth-sized planet was discovered earlier, and the first class James Webb Space Telescope has already decided to observe the atmosphere. The atmospheres of Earth-sized planets are expected to be equally important. Norio Narita, professor of exoplanetary astronomy at the University of Tokyo, who is part of the research team, said, “In the solar system, on Earth, Venus and Mars, volcanic activity caused gas, mainly carbon dioxide, to become out. inside the planet and create an atmosphere. We can use observations to check what kind of atmosphere is formed on planets outside the solar system.” (Tomoyasu Sakakibara)