Volcanoes could ignite the planet’s night sky

On Earth, it is not just plate tectonics that are responsible for the rise of mountains and earthquakes. It is also an essential part of the circle that carries matter from the inside of the planet to the surface and atmosphere, and then transports it back under the Earth’s crust. Tectonics therefore have an important influence on the conditions that ultimately make a habitation on Earth.

To date, researchers have found no evidence of global tectonic activity on planets outside our solar system. A team of researchers led by Tobias Meier from the Center for Space and Space (CSH) at the University of Bern and with the participation of ETH Zurich, University of Oxford and the National Research Capability Center NCCR PlanetS has now found evidence of the patterns planetary interior flow, located 45 light-years from Earth: LHS 3844b. Their findings were published in Letters of the Astrophysical Journal.

Big difference and no atmosphere

“Monitoring for signs of tectonic activity is very difficult, as they are usually hidden under an atmosphere,” explains Meier. However, recent results have suggested that LHS 3844b may not have an atmosphere. Slightly larger than Earth and seemingly rocky, it moves around its star so closely that one side of the planet is in steady daylight and the other side on a permanent night – just as one side of the Moon always facing the Earth. Without any atmosphere protecting it from the intense radiation, the surface becomes very hot: it can reach up to 800 ° C on the daytime side. The night side, on the other hand, is freezing. Temperatures can drop below less than 250 ° C. “We thought that this adverse temperature difference could affect the flow of materials in the interior of the planet”, Meier recalls.

To test their theory, the team ran computer simulations with different strengths of materials and internal heating sources, such as heat from the planet’s core and the decay of radioactive elements. The symbols included the large surface temperature difference placed by the host star.

Flowing inside the planet from one hemisphere to another

“Most symbols showed that there was only flow up on one side of the planet and flow down on the other side. So material was flowing from one hemisphere to the other,” Meier reports. Surprisingly, the instructions were not always the same. “Based on what we are used to from Earth, you would expect the material on the hot day to be lighter and therefore flow up and vice versa”, co-author Dan Bower of the University of Bern and the NCCR PlanetS explaining. However, some team symbols showed the opposite side of a stream. “This inconvenient result is initially due to the change in viscosity with temperature: cold material is harder and therefore does not want to bend, break or penetrate into the warm material, however, is so slow – so even hard rock becomes more mobile when heated – and can easily flow into the interior of the planet “, Bower edits. Either way, these results show how the surface of a planet and its interior can exchange material under very different conditions from those on Earth.

Volcanic hemisphere

The flow of such material may be adversely affected. “Regardless of which side of the planet the material flows up, a lot of volcanism would be expected on that particular side,” Bower says. It follows “similar deep renewal currents on Earth’s volcanic activity in Hawaii and Iceland”. So you would think of a hemisphere with countless volcanoes – a volcanic hemisphere so to speak – and one with almost none.

“Our symbols show how these patterns might appear, but it would need to confirm a more detailed study. For example, with a map with a higher resolution of surface temperature that could indicate better rise from volcanism, or the discovery of volcanic gases.This is something we hope future research will help us to understand “, Meier concludes.

Bernese space exploration: With the world’s elite since the first moon landed

When the second, “Buzz” Aldrin, released the lunar model on July 21, 1969, his first act was to set up a Bernese Solar Wind Composition (SWC) test also known as the “solar wind supply” by placing it in the moon’s ground, even before the American flag. This experiment, which was planned and the results of Dr. Dr. Johannes Geiss and his team from the University of Bern Institute of Physics, the first major in the history of Bernese space study.

Since then the study of Bernese place has been among the elite of the world. The numbers are impressive: 25 times instruments were introduced into the upper atmosphere and ionosphere using rockets (1967-1993), 9 times into the stratosphere by balloon flights (1991-2008), more 30 instruments fly on space probes, and with CHEOPS the University of Bern shares responsibility with ESA for an overall mission.

The successful work of the Department of Space Research and Planning Sciences (WP) of the University of Bern Institute of Physics was underpinned by the establishment of a university capability center, the Center for Space and Space (CSH). The Swiss National Fund has also donated PlanetS to the National Center for Research Capability (NCCR), which they co-manage with the University of Geneva.

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