New Delhi: Astronomers have found an Earth-like exoplanet that could be covered with volcanoes. The planet, named LP 791-18 d, is about 90 light-years away from us.
The planet could undergo volcanic outbursts as often as Jupiter’s moon ‘Io’ — the most volcanically active body in our solar system.
Researchers from the University of Montreal found and studied the planet using data from National Aeronautics and Space Administration’s (NASA) TESS (Transiting Exoplanet Survey Satellite) and retired Spitzer Space Telescope, as well as a suite of ground-based observatories. The observations were published in the journal Nature this week.
The planet orbits a small red dwarf star in the southern constellation crater. The team estimates it’s only slightly bigger and heavier than Earth. It is tidally locked, which means one of its sides always faces its star.
This is the third planet to be discovered in this star system called LP 791-18 b and c. The inner planet b is about 20 per cent bigger than Earth. The outer planet c is about 2.5 times Earth’s size and more than seven times its mᴀss.
During each orbit, planets d and c pᴀss very close to each other. Each close pᴀss by the more mᴀssive planet c produces a gravitational tug on planet d, making its orbit somewhat elliptical.
On this elliptical path, planet d is slightly deformed every time it goes around the star. These deformations can create enough internal friction to substantially heat the planet’s interior and produce volcanic activity at its surface. This is similar to what happens on Jupiter’s moon Io.
Planet d sits on the inner edge of the habitable zone, the traditional range of distances from a star where scientists hypothesise liquid water could exist on a planet’s surface.
If the planet is as geologically active, as the research team suspects, it could maintain an atmosphere. Temperatures could drop enough on the planet’s night side for water to condense on the surface.
