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1. Radiogenic heating sustains long-lived volcanism and magnetic dynamos in super-Earths

   https://doi.org/10.1126/sciadv.ado7603  

   Luo, Haiyang; O’Rourke, Joseph G; Deng, Jie (September 2024, Science Advances)

   Radiogenic heat production is fundamental to the energy budget of planets. Roughly half of the heat that Earth loses through its surface today comes from the three long-lived, heat-producing elements (potassium, thorium, and uranium). These three elements have long been believed to be highly lithophile and thus concentrate in the mantle of rocky planets. However, our study shows that they all become siderophile under the pressure and temperature conditions relevant to the core formation of large rocky planets dubbed super-Earths. Mantle convection in super-Earths is then primarily driven by heating from the core rather than by a mix of internal heating and cooling from above as in Earth. Partitioning these sources of radiogenic heat into the core remarkably increases the core-mantle boundary (CMB) temperature and the total heat flow across the CMB in super-Earths. Consequently, super-Earths are likely to host long-lived volcanism and strong magnetic dynamos. 

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2. Shaping Magnetic Liquid Metals Into 3D Leakage‐Free, Shape‐Programmable Structures and Electronics

   https://doi.org/10.1002/aelm.202500166  

   Lu, Yongyu; Wang, Zizheng; Abdulla, Vagif; Pfund, Jacob; Lu, Shao‐Hao; Li, Yi; Zhang, Xincheng; Fennell, Gavin; Zhang, Yuxuan; Jain, Menka; et al (November 2025, Advanced Electronic Materials)

   Abstract Liquid metals (LMs), renowned for their high conductivity and large deformability, find increasing applications including in flexible electronics and soft robotics. One critical process in these applications is the precise patterning of LMs into desired shapes. Yet, existing LM patterning techniques predominantly focus on 2D patterns due to challenges posed by the inherent fluidity and leakage of LMs. Here, we introduce an approach that bypasses these limitations, enabling the creation of complex 3D leakage‐free LM structures. This is achieved through mechanical programming of 2D magnetically immobilized LM paste formed via incorporating magnetic particles into LMs. Such composite effectively resists leakage due to the combined effect of strong magnetic inter‐attraction within the porous magnetic networks and the high surface tension of LMs, while retaining the high conductivity. Diverse freestanding magnetic LM structures, obtained upon LM solidification at ambient temperature, dynamically morph between their 2D and various 3D configurations through multiple cycles of induction heating and magnetic‐assisted reprogramming, featuring large compression resistance and self‐healing capabilities. Potential applications of these leakage‐resistant, shape‐adaptable structures are demonstrated through a helical magnetic LM antenna, which showcases its efficiency in wireless communication and energy harvesting. 

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3. Melting and density of MgSiO3 determined by shock compression of bridgmanite to 1254GPa

   https://doi.org/10.1038/s41467-021-21170-y  

   Fei, Yingwei; Seagle, Christopher T.; Townsend, Joshua P.; McCoy, Chad A.; Boujibar, Asmaa; Driscoll, Peter; Shulenburger, Luke; Furnish, Michael D. (December 2021, Nature Communications)

   null (Ed.)

   Abstract The essential data for interior and thermal evolution models of the Earth and super-Earths are the density and melting of mantle silicate under extreme conditions. Here, we report an unprecedently high melting temperature of MgSiO 3 at 500 GPa by direct shockwave loading of pre-synthesized dense MgSiO 3 (bridgmanite) using the Z Pulsed Power Facility. We also present the first high-precision density data of crystalline MgSiO 3 to 422 GPa and 7200 K and of silicate melt to 1254 GPa. The experimental density measurements support our density functional theory based molecular dynamics calculations, providing benchmarks for theoretical calculations under extreme conditions. The excellent agreement between experiment and theory provides a reliable reference density profile for super-Earth mantles. Furthermore, the observed upper bound of melting temperature, 9430 K at 500 GPa, provides a critical constraint on the accretion energy required to melt the mantle and the prospect of driving a dynamo in massive rocky planets. 

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4. Discovery of a Nearby Habitable Zone Super-Earth Candidate Amenable to Direct Imaging

   https://doi.org/10.3847/1538-3881/ae0e20  

   Beard, Corey; Robertson, Paul; Lubin, Jack; Ford, Eric B; Mahadevan, Suvrath; Stefansson, Gudmundur; Wright, Jason T; Wolf, Eric; Kofman, Vincent; Venkatesan, Vidya; et al (October 2025, The Astronomical Journal)

   Abstract We present the discovery of GJ 251 c, a candidate super-Earth orbiting in the habitable zone (HZ) of its M dwarf host star. Using high-precision Habitable-zone Planet Finder and NEID RVs, in conjunction with archival RVs from the Keck I High Resolution Echelle Spectrometer, the Calar Alto High-resolution Search for M dwarfs with Exoearths with Near-infrared and optical Echelle Spectrograph, and the Spectropolarimétre Infrarouge, we improve the measured parameters of the known planet, GJ 251 b (P_b= 14.2370 days; $m\sin \left(i\right)$= 3.85 ${}_{-0.33}^{+0.35}$M_⊕), and we significantly constrain the minimum mass of GJ 251 c, placing it in a plausibly terrestrial regime (P_c= 53.647 ± 0.044 days; $m\sin i_c$= 3.84 ± 0.75M_⊕). Using activity mitigation techniques that leverage chromatic information content, we perform a color-dependent analysis of the system and a detailed comparison of more than 50 models that describe the nature of the planets and stellar activity in the system. Due to GJ 251’s proximity to Earth (5.5 pc), next generation, 30 meter class telescopes will likely be able to image terrestrial planets in GJ 251’s HZ. In fact, GJ 251 c is currently the best candidate for terrestrial, HZ planet imaging in the northern sky. 

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5. The Thermal Conductivity of Bridgmanite at Lower Mantle Conditions Using a Multi‐Technique Approach

   https://doi.org/10.1029/2024JB028823  

   Edmund, Eric; Chuvashova, Irina; Konôpková, Zuzana; Husband, Rachel; Strohm, Cornelius; Appel, Karen; Bähtz, Carsten; Ball, Orianna; Bouffetier, Victorien; Brugman, Kara; et al (June 2024, Journal of Geophysical Research: Solid Earth)

   Abstract The thermal conductivity of bridgmanite, the primary constituent of the Earth's lower mantle, has been investigated using diamond anvil cells at pressures up to 85 GPa and temperatures up to 3,100 K. We report the results of time‐domain optical laser flash heating and X‐ray Free Electron Laser heating experiments from a variety of bridgmanite samples with different Al and Fe contents. The results demonstrate that Fe or Fe,Al incorporation in bridgmanite reduces thermal conductivity by about 50% in comparison to end‐member MgSiO₃at the pressure‐temperature conditions of Earth's lower mantle. The effect of temperature on the thermal conductivity at 28–60 GPa is moderate, well described as , whereais 0.2–0.5. The results yield thermal conductivity of 7.5–15 W/(m × K) in the thermal boundary layer of the lowermost mantle composed of Fe,Al‐bearing bridgmanite. 

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