Like the volcanic planet Mustafar from Star wars, half of exoplanet 3844b could be covered with active volcanoes. This planet, discovered in 2019, could be the first world we know of, outside of the solar system, to have plate tectonics, which guides much of the geology over our own world.
On Earth, plate tectonics cause earthquakes and build mighty mountains, and it carries material below the Earth’s surface, expelling material into the crust and atmosphere. This movement of the Earth’s crustal plates also plays a crucial role in the return of these materials underground, completing the geological process.
This tectonic cycle, essential to the conduct of climatic conditions on Earth, has never been observed in a world outside our solar system – until now.
Hot and cold operation
Located just 45 light years from Earth, LHS 3844b is said to have no atmosphere. This makes it a little easier for astronomers to see the tectonic processes taking place in this distant world. Even under the best conditions, these measures are state-of-the-art.
“The first mission to Mars didn’t expect to find craters and river valleys, and yet they did. The first mission to Jupiter didn’t expect to find oceanic worlds and volcanic worlds, but they did. – Alan Stern
This volcano planet, made up mostly of rocks like our own world, is slightly larger than Earth.
This world orbits so close to its star that it is locked to the tide – eternally facing one side towards its star parent, like the face on the Moon always points to Earth. For this reason, one side of LHS 3844b is constantly heated, while the other side remains perpetually frozen. While the sunny side of this world burns at temperatures of 800 degrees Celsius (1470 Fahrenheit), nighttime temperatures drop to -250 ° C (-420 ° F).
The researchers suspected that this extreme temperature difference could lead to geological flows within this volcanic planet.
An international team led by Tobias Meier from the Center for Space and Habitability (CSH) at the University of Bern developed computer models to test the theory.
Models showed that the geology within LHS 3844b would likely cause mantle material to flow to one side of the exoplanet to the other. Logically, one would think that the hotter material on the “day side” of the world would be lighter, which would make it more likely to rise on that side. However, some of the simulations showed the exact opposite pattern, resulting in a night filled with volcanoes.
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“This initially counter-intuitive result is due to the change in viscosity with temperature: the cold material is more rigid and therefore does not want to bend, break or subduct inside. Hot material, however, is less viscous – so even solid rock becomes more mobile when heated – and can easily flow into the interior of the planet ”. Dan Bower at the University of Bern explains.
A rise of material on one side of the planet could lead to active volcanism in that hemisphere, the researchers determined. This would be similar to the processes that drive the highly volcanic regions of Hawaii and Iceland. Such conditions could lead to the development of a volcanic world, with one side covered in volcanoes, while the other half remains almost bare.
It’s like Pompeii without the tourist food …
Proof for recent volcanism has been spotted on Venus and Io. This new discovery shows how tectonic activity on another world can be significantly different from geological activity on Earth.
“Earth is the only known planet with active plate tectonics, but observations of exoplanets may provide information on the diversity of tectonic regimes beyond the solar system,” the researchers describe in an article published in Letters from the astrophysical journal.
In the video above, an interview with Dr. Laurent Montesi, a geologist at the University of Maryland, who discovered evidence of recent volcanic activity on Venus. (Video credit: The Cosmic Companion).
Volcanoes play an essential role in the development and evolution of life on Earth, and these sometimes explosive centers can modify our climate, even today, under the right conditions.
“When Mount Pinatubo erupted in the Philippines on June 15, 1991, approximately 20 million tonnes of sulfur dioxide and ash particles were projected more than 20 km high into the atmosphere. The eruption caused destruction and loss of life on a large scale. Gases and solids injected into the stratosphere circled the globe for three weeks ”. NASA reports.
Likewise, volcanoes would probably be a guiding factor in the development of life on other worlds. Although LHS 3844b is the first exoplanet known to show plate tectonics, other volcanic planets may soon be discovered by astronomers in search of the vast open-air prairie.
This article was originally published on The cosmic companion by James maynard, founder and publisher of The Cosmic Companion. He was born in New England and became a desert rat in Tucson, where he lives with his lovely wife, Nicole and Max the Cat. You can read this original piece here.
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