Astronomers May Have Found The First Evidence For Tectonic Activity On An Exoplanet

Science & Tech 20:30 06.03.2021

On Earth, the heat generated from the radioactive decay of elements in Earth's mantle drives convection currents, pushing and dragging large plates of Earth's crust around. When the plates collide, mountains form, and parts of Earth's crust are recycled into the mantle. When the plates are pushed apart, the partially molten mantle rises upward to fill the gap. Plate tectonics is an essential part of the cycle that brings material from the planet's interior to the surface and the atmosphere, and then transports it back beneath the Earth's crust. Tectonics thus has a vital influence on the energy and matter transfer that ultimately makes Earth habitable.

Until now, 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 Habitability (CSH) at the University of Bern and with the participation of ETH Zurich, the University of Oxford, and the National Center of Competence in Research NCCR PlanetS has now found evidence of the flow patterns inside a planet, located 45 light-years from Earth: LHS 3844b. Their results were published in The Astrophysical Journal Letters.

LHS 3844b is an exoplanet orbiting the red dwarf star LHS 3844, discovered using the Transiting Exoplanet Survey Satellite. It orbits its parent star once every 11 hours, and its radius is 1.32 times that of Earth. It has a low albedo, indicating that its surface may resemble that of the Moon or Mercury.

"Observing signs of tectonic activity is very difficult, because they are usually hidden beneath an atmosphere", Meier explains. However, recent results suggested that LHS 3844b probably does not have an atmosphere. Slightly larger than Earth and likely similarly rocky, it orbits around its star so closely that one side of the planet is gravitationally locked towards its sun. One hemisphere of the planet is in constant daylight and the other in permanent night. With no atmosphere shielding it from the intense radiation, the surface gets blisteringly hot: it can reach up to 800 degrees Celsius on the dayside. Common rocks, like granite and basalt, melt at temperatures of 900 to 1,200 degrees Celsius. The night side, on the other hand, is freezing. Temperatures there might fall below minus 250 degrees Celsius. "We thought that this severe temperature contrast might affect material flow in the planet's interior", Meier recalls.

Cool rocks are brittle and tend to break, becoming much more liquid-like as they heat up. The team ran computer simulations with different strengths of material and internal heating sources, such as heat from the planet's core and the decay of radioactive elements. The simulations also included the large temperature contrast on the surface imposed by the host star.

"Most simulations showed that there was only upwards flow on one side of the planet and downwards flow on the other. Material therefore flowed from one hemisphere to the other", Meier reports. Surprisingly, the direction was not always the same. "Based on what we are used to from Earth, you would expect the material on the hot dayside to be lighter and therefore flow upwards and vice versa", co-author Dan Bower at the University of Bern and the NCCR PlanetS explains. Yet, some of the teams' simulations also showed the opposite flow direction. "This initially counter-intuitive result is due to the change in viscosity with temperature: cold material is stiffer and therefore doesn't want to bend, break or subduct into the interior. Warm material, however, is less viscous - so even solid rock becomes more mobile when heated - and can readily flow towards the planet's interior", Bower elaborates. Either way, these results show how a planetary surface and interior can exchange material under conditions very different from those on Earth.

As a result, the researchers suggest that LHS 3844b could have one entire hemisphere covered in volcanoes comparable to terrestrial volcanism as found in Hawaii and Iceland. Here mantle-plumes form very hot lava with low viscosity.

"Our simulations show how such patterns could manifest, but it would require more detailed observations to verify," says Meier.

"For example, with a higher-resolution map of surface temperature that could point to enhanced outgassing from volcanism, or detection of volcanic gases. This is something we hope future research will help us to understand."

IEPF issued a statement regarding Azerbaijani children at the UN Human Rights Council

News line

Drone attack in Russia's Udmurtia leaves three dead, dozens injured
20:15 01.07.2025
Billionaire Musk vows to launch new political party if controversial Trump bill passes Congress
20:00 01.07.2025
Broken Friendship: Azerbaijan–Russia Relations INTERVIEW
19:40 01.07.2025
Baku to host D-8 Youth Forum in July
19:30 01.07.2025
Speaker: Armenia should seriously begin discussing issue of stopping broadcasting Russian TV channels
19:20 01.07.2025
Russian Foreign Ministry: Azerbaijani envoy handed verbal note
19:15 01.07.2025
Azerbaijan signs $173.5M loan agreement with WB for renewable energy project
19:00 01.07.2025
Azerbaijan, Uzbekistan ink several documents to diversify economic partnership
18:45 01.07.2025
Another group of Ukrainian children arrive in Azerbaijan for rehabilitation
18:15 01.07.2025
IEPF Launches a Series of Trainings for NGOs
18:14 01.07.2025
Sahil Babayev: Azerbaijan aims to become green energy exporter
18:00 01.07.2025
Azerbaijani minister: Youth action plan to be drafted at international event in Aghdam
17:45 01.07.2025
Azerbaijan launches criminal case into killing of Azerbaijani brothers in Russia
17:30 01.07.2025
European diplomats visit West Bank town after deadly attack by Israeli settlers
17:15 01.07.2025
Poland’s president calls on gov’t to stop entry of migrants from Germany
17:00 01.07.2025
Artists, writers urge UK government not to ban pro-Palestine group
16:45 01.07.2025
China's Communist Party tops 100 million members in ‘significant milestone’
16:30 01.07.2025
China says ‘complicated’ boundary dispute with India will take time to resolve
16:15 01.07.2025
Severe weather batters Italy, leaving two dead and multiple regions on alert
16:00 01.07.2025
Azerbaijan detains Russian citizens in Baku suspected of drug trafficking, online fraud
15:50 01.07.2025
China sanctions former Philippines senator over 'egregious conduct' on Beijing-related issues
15:30 01.07.2025
Meta fined over $512,000 by Taiwan for lack of transparency over advertisers
15:15 01.07.2025
Trump says Musk would ‘head back to South Africa’ without US subsidies for EVs
15:00 01.07.2025
Azerbaijani brothers murdered in Russia hit with blunt instrument, examinations reveal
14:45 01.07.2025
Kazakhstan commends top-tier organization of ECO Youth Forum in Azerbaijan's Aghdam
14:30 01.07.2025
U.S. Charge d'Affaires hails Azerbaijan’s support in ensuring safe evacuation country's citizens from Iran
14:15 01.07.2025
Slovakia appoints Azerbaijani native as ambassador to Baku
14:00 01.07.2025
Fitch reveals forecast for Azerbaijan's state budget deficit in 2025
13:45 01.07.2025
WSJ: Amazon is on the cusp of using more robots than Humans in its warehouses
13:30 01.07.2025
Politico: EC ready to allow countries to restrict access to social networks by age
13:15 01.07.2025
Azerbaijani brothers murdered in Russia hit with blunt instrument, examinations reveal
13:00 01.07.2025
Azerbaijani official elected vice-president of international conference
12:45 01.07.2025
US approves $510M sale of munitions guidance kits to Israel
12:30 01.07.2025
Death toll in India factory blast rises to 34
12:25 01.07.2025
Azerbaijani ambassador leaves Russian Foreign Ministry building
12:15 01.07.2025
Iranian president to attend ECO summit in Azerbaijan's Khankandi
12:10 01.07.2025
Russia summons Azerbaijani ambassador
12:00 01.07.2025
Iran-linked hackers threaten to release Trump aides' emails
11:45 01.07.2025
Israeli strikes on Gaza Strip leave 95 Palestinians killed
11:30 01.07.2025
Israel shoots down over 1,000 Iranian drones — permanent representative to UN
11:15 01.07.2025
Hamısı