The gravity of a neighboring planet can heat the planet's interior, promoting volcanic activity on the surface. An Earth-size sphere outside our solar system has been found by astronomers and may be covered by volcanoes. Known as LP 791-18 d, the planet has the potential to have the same level of volcanic eruptions as Jupiter's moon Io, the most volcanically active body in our solar system.
The researchers used information from NASA's TESS (Transiting Exoplanet Survey Satellite) and the retired Spitzer Space Telescope, as well as a number of ground-based observatories, to explore and study the planet.
Merrin Peterson of the University of Montreal Trottier Exoplanet Research Institute (iREx) served as lead author of the study. The article was published May 17 in the scientific journal Nature.
According to co-author and iREx professor of astronomy Björn Benneke, who organized and led the project, the LP 791-18 d is tidally locked, meaning it always faces its star on the same side. “The daytime side will probably be too hot for liquid water to exist on the surface. But with the amount of volcanic activity we believe exists throughout the planet, it's possible for an atmosphere to exist and water to be concentrated on the night side.
LP 791-18 d orbits a small red dwarf star 90 light-years away in the southern constellation Crater. According to the team, it is only marginally larger and more massive than Earth.
Prior to this discovery, astronomers were aware of two more planets in the system known as LP 791-18 b and c. The planet called b, which is 20% larger than Earth, is the inner planet. The outer planet, called C, is more than seven times larger and about 2,5 times the size of Earth.
Planets d and c pass very close to each other during each orbit. With each close pass of major planet c, planet d experiences a gravitational pull, causing planet d's orbit to become somewhat elliptical.
Each time planet D orbits the star in this elliptical course, it gradually deviates from its original shape. The internal friction caused by these deformations has the potential to significantly heat the planet's interior and cause volcanic activity on its surface. Io also receives similar influences from Jupiter and some of its moons.
The habitable zone is the traditional range of distances from a star that scientists predict can contain liquid water on a planet's surface, with planet d at the inner edge of this zone. The planet may have an atmosphere if it is as geologically active as the research team believes. On the night side of the planet, temperatures may be low enough for water to condense on the surface.
The team believes planet d is a particularly strong possibility for atmosphere surveys by the mission, and planet c has already been cleared for observation time in the James Webb Space Telescope.
Whether tectonic or volcanic activity is essential for life is in astrobiology, a discipline that broadly studies the origin of life on Earth and beyond, according to Jessie Christiansen, a research fellow at NASA's Exoplanet Science Institute at Caltech in Pasadena. a key issue. These activities “possibly in addition to providing an atmosphere, they can also church up materials that would otherwise sink down and become trapped in the crust, including what we consider important to life, such as carbon.”
One of the last data points the Spitzer satellite collected before it was terminated in January 2020 was observations of the system.
"It's surprising to read that discoveries and publications continue years after Spitzer's mission ends," said Joseph Hunt, Spitzer project manager at NASA's Jet Propulsion Laboratory in Southern California. “This clearly demonstrates the achievements of our top engineers and scientists. Together they created a spacecraft and a dataset that is still useful to the astrophysical community.
Günceleme: 22/05/2023 13:21