You may not be too familiar with the planet LHS 3844b, but it now has its own distinction: It is the first planet outside of our solar system that astronomers believe may have evidence of tectonic activity.
That proof is a series of advanced simulations based on observations of the rocky planet, which is slightly larger than Earth. Important for this particular study is that it doesn’t look like the exoplanet has an atmosphere.
That leaves half of LHS 3844b permanently exposed to the sun and can mean temperatures up to about 800 degrees Celsius (1472 degrees Fahrenheit) on the ‘day’ side, and about minus 250 degrees Celsius (minus 418 degrees Fahrenheit) at night. -time ‘side.
“We thought that this strong temperature contrast could influence the material flow inside the planet,” said astronomer Tobias Meier of the University of Bern in Switzerland.
Based on phase curve observations of the planet’s brightness and possible temperatures, and computer models simulating various possible tectonic materials and heat sources, Meier and his colleagues believe there is a flow of underground material on a hemispherical scale.
Most of the simulations the researchers ran only showed an updraft on one side of the planet and only a downward flow on the other, but in some scenarios that was reversed – a surprising find, and one that doesn’t match tectonic motion. on earth.
“Based on what we are used to from Earth, you would expect the material to be lighter on hot days and therefore flow upwards and vice versa,” said geophysicist Dan Bower of the University of Bern.
The underlying reason is the changing temperature of the mantle material as it moves, with colder rock becoming stiffer and less mobile, and warmer rock becoming much more fluid as it gets warmer. The scientists say the shifting of surface and material can lead to some pretty incredible tectonic activity.
“No matter which side of the planet the material flows upward, you would expect a great deal of volcanism on that side,” says Bower.
As a result, scientists suggest that LHS 3844b could have covered an entire hemisphere with volcanoes, while the other side shows hardly any volcanic activity – all because of the intense temperature contrast around the planet.
The kind of upwelling these volcanoes would create is similar to what we see on Earth, but only in specific places, such as Hawaii and Iceland. In more general terms, the tectonic motion these models suggest is unlike anything in our solar system.
As more powerful space telescopes come online and our understanding of exoplanets improves, further observations and research should help confirm what is happening across the surface of LHS 3844b – and whether it is really half-covered with volcanoes.
“Our simulations show how such patterns might manifest, but more detailed observations are needed to verify this,” says Meier.
“For example, with a higher resolution surface temperature map that could indicate enhanced volcanic outgassing, or volcanic gas detection. We hope future research will help us understand this.”
The research is published in the Astrophysical Journal Letters