Study Findings: Electrical Conductivities of (Mg,Fe)O at Extreme Pressures and Implications for Planetary Magma Oceans

Posted on by onespaceman2000
Image (Credit): Artist’s rendering of deep layers of molten rock inside a super-earth generating powerful magnetic fields. (University of Rochester Laboratory for Laser Energetics illustration / Michael Franchot)

Nature Astronomy abstract of study findings:

During planet formation, planets undergo many impacts that can generate magma oceans. When these crystallize, part of the magma densifies via iron enrichment and migrates to the core–mantle boundary, forming an iron-rich basal magma ocean (BMO). The BMO could generate a dynamo in early Earth and super-Earths if the electrical conductivity of the BMO, which is thought to be sensitive to its Fe content, is sufficiently high. To test this hypothesis, here we conduct laser-driven shock experiments on ferropericlase (Mgx,Fe1−x)O (0.95 ≤ x ≤ 1) as an Fe-rich BMO analogue, perform density functional theory molecular dynamics simulations on MgO and calculate the long-term evolution of super-Earths. We find that the d.c. conductivities of MgO and (Mg,Fe)O are indistinguishable between 467 GPa and 1,400 GPa, despite previous predictions. We predict that super-Earths larger than 3–6 Earth masses can produce BMO-driven dynamos that are almost one order of magnitude stronger than core-driven dynamos for several billion years.

Citation: Nakajima, M., Harter, S.K., Jasko, A.V. et al. Electrical conductivities of (Mg,Fe)O at extreme pressures and implications for planetary magma oceans. Nat Astron (2026).

https://doi.org/10.1038/s41550-025-02729-x

Study-related stories:

University of Rochester – “Hidden Magma Oceans Could Shield Rocky Exoplanets from Harmful Radiation”

Earth Sky – “Powerful Magnetic Fields on Super-Earths Could Boost Chances of Life”

Universe Today – “Deep Magma Oceans Could Help Make Super-Earths Habitable”

Space Quote: NASA Astronaut Suni Williams Retires

Posted on by onespaceman2000
Image (Credit): NASA astronauts Suni Williams and Butch Wilmore. (NASA)

“It is hard to imagine people arguing down there, not to mention fighting. It looks so peaceful… so calm down on earth. From space, there are no borders that you can see. We are lucky to live on such a planet and we should not take it for granted. After my space experience, I am a lot more tolerant of people and opinions, of everything.”

-A 2007 statement by NASA astronaut Suni Williams, who announced her retirement from the agency earlier today. Although she spend 27 years with NASA, she will probably be best remembered for her Boeing Starliner flight to the International Space Station in 2024 that was supposed to last one week but became nine months instead. It was a replay of Gilligan’s Island in space. Her fellow astronaut on that troubled flight, Butch Wilmore, retired from NASA last August.

Space Stories: A Peruvian Solar Observatory, NASA Rocket Traffic, and a Reborn Back Hole

Posted on by onespaceman2000
Image (Credit): Aerial view of the fortress at Chankillo. (Servicio Aerofotográfico Nacional, Lima)

Here are some recent space-related stories of interest.

—Discover Magazine: “The Earliest-Known Astronomical Observatory in the Americas May Offer New Insights“

There was a time when Stonehenge was believed to be a kind of “Neolithic computer.” Archaeology has since corrected that misconception. Today, the evidence points strongly in another direction: to an arid hill in the Casma Valley on Peru’s northern coast, about 200 miles north of Lima. There stands Chankillo, a complex built around 250 B.C.E., considered the earliest known solar observatory in the Americas and the clearest known example of a monument designed to track the sun’s position throughout the entire year, according to a study in Science. Modest in appearance and largely absent from tourist posters and classic postcards, Chankillo has renewed attention as archaeologists report preliminary findings from ongoing excavations.

—CBS News: “NASA Juggling Piloted Moon Mission and Space Station Crew Replacement Flight“

With a space station medical evacuation safely completed, NASA is focused on two challenging missions proceeding in parallel: launching four astronauts on a flight around the moon, at the same time as the agency is planning to send four replacement astronauts to the International Space Station...The Artemis 2 mission and Crew 12’s planned space station flight present a unique challenge for NASA. The agency has not managed two piloted spacecraft at the same time since a pair of two-man Gemini capsules tested rendezvous procedures in low-Earth orbit in 1965. The agency has never flown a deep space mission amid another launch to Earth orbit.

—Royal Astronomical Society: “‘Reborn’ Black Hole Spotted ‘Erupting like Cosmic Volcano’“

One of the most vivid portraits of “reborn” black hole activity – likened to the eruption of a “cosmic volcano” spreading almost one million light-years across space – has been captured in a gigantic radio galaxy. The dramatic scene was uncovered when astronomers spotted the supermassive black hole at the heart of J1007+3540 restarting its jet emission after nearly 100 million years of silence.

Note: Please ignore the previous posting for today about the Apollo 17 mission. It’s a good story, but I will need to retell it at another time (that is, on December 19th).

Video: Brian Cox Talks About Alien Life – A 2026 Special

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Image (Credit): Professor Brian Cox discussing the evolution of intelligence. (Science Time channel)

If you have followed the career of English physicist Brian Cox, then you know he is a dynamic speaker who has hosted several series on astronomy, including Wonders of the Solar System and Wonders of the Universe.

In this short video from Science Time channel, “Brian Cox Talks About Alien Life – A 2026 Special,” Professor Cox walks the viewer through the chances of finding intelligent life among the 60 billion exoplanets in our galaxy that lie within the habitable zone. To be clear, he is not very optimistic.

The series does not cover much new ground except for some hopeful comments about the James Webb Space Telescope investigating the atmospheres of exoplanet (with Professor Cox wondering whether we will find life on an exoplanet before we find it on Mars). Even so, it is still enjoyable to spend a little bit of time playing around with the Fermi Paradox again.

One of the more intriguing ideas being discussed here and elsewhere is the idea that we may not want to limit our ideas to biological life. The longevity of a civilization may be dependent on its ability to evolve from carbon-based to silicon-based lifeforms. While not explicitly discussed in the video, that could broaden our search beyond a star’s habitable zone yet also frustrate our attempts to find biological signatures in an exoplanet’s atmosphere.

Again, it is worth your time to listen in. I would just ignore the goofy animations that accompany the discussion.