Results 41 to 50 of about 467 (180)

Devolatilization of extrasolar planetesimals by 60Fe and 26Al heating [PDF]

Whilst the formation of Solar system planets is constrained by meteoritic evidence, the geophysical history of low-mass exoplanets is much less clear.
Eatson, Joseph W., Gerya, Taras V., Lichtenberg, Tim, Parker, Richard J.   +3 more
core   +8 more sources

Revisiting the Relationship Between Rocky Exoplanet and Stellar Compositions: Reduced Evidence for a Super-Mercury Population

The Astronomical Journal
Planets and the stars they orbit are born from the same cloud of gas and dust, and the primordial compositions of rocky exoplanets have been assumed to have iron and refractory abundance ratios consistent with their host star. To test this assumption, we
Casey L. Brinkman, Alex S. Polanski, Daniel Huber, Lauren M. Weiss, Diana Valencia, Mykhaylo Plotnykov   +5 more
doaj   +1 more source

Hydroxylation and Hydrogen Diffusion in Lunar Samples: Spectral Measurements During Proton Irradiation

Journal of Geophysical Research: Planets, Volume 130, Issue 3, March 2025.
Abstract Widespread OH/H2 ${\mathrm{H}}_{2}$O has been detected across the lunar surface, but its origin remains a matter of active investigation. We present laboratory measurements of Apollo‐17 samples LS 78421 and LS 73131 that demonstrate, in situ, the formation of OH/H2 ${\mathrm{H}}_{2}$O during irradiation by energetic hydrogen ions similar to ...
Li Hsia Yeo, Anastasis Georgiou, Liam Morrissey, William Farrell, Jason McLain   +4 more
wiley   +1 more source

Atomic-scale mixing between MgO and H$_2$O in the deep interiors of water-rich planets [PDF]

, 2021
Water-rich planets exist in our Solar System (Uranus and Neptune) and are found to be common in the extrasolar systems (some of the sub-Neptunes). In conventional models of these planets a thick water-rich layer is underlain by a separate rocky interior.
Pakhomova, Anna, Lee, Yongjae, Liu, Zhenxian, Kim, Taehyun, Speziale, Sergio, Liermann, Hanns-Peter, Prakapenka, Vitali, Chariton, Stella, Shim, Sang-Heon   +8 more
core   +1 more source

Detecting Biosignatures in Nearby Rocky Exoplanets Using High-contrast Imaging and Medium-resolution Spectroscopy with the Extremely Large Telescope

The Astronomical Journal, 2023
In the upcoming decades, one of the primary objectives in exoplanet science is to search for habitable planets and signs of extraterrestrial life in the Universe.
Huihao Zhang, Ji Wang, Michael K. Plummer   +2 more
doaj   +1 more source

Superhabitable Planets Around Mid‐Type K Dwarf Stars Enhance Simulated JWST Observability and Surface Habitability

Astronomische Nachrichten, Volume 346, Issue 2, February 2025.
ABSTRACT In our search for life beyond the Solar System, certain planetary bodies may be more conducive to life than Earth. However, the observability of these “superhabitable” (SH) planets in the habitable zones around K dwarf stars has not been fully modeled. This study addresses this gap by modeling the atmospheres of SH exoplanets.
Iva Vilović, Jayesh Goyal, René Heller, Fanny Marie von Schauenburg   +3 more
wiley   +1 more source

A Link between Rocky Planet Density and Host Star Chemistry

The Astronomical Journal
Planets and their host stars form from the same cloud of gas and dust, so we assume that their chemical compositions are linked. However, a clear correlation between rocky planet interior properties and host star chemistry remains elusive for planets ...
Aida Behmard, Casey L. Brinkman, Soichiro Hattori, Ryan A. Rubenzahl, Megan Bedell   +4 more
doaj   +1 more source

The Process We Call Earth: Relationships Between Dynamic Feedbacks and the Search for Gaiasignatures in a New Paradigm of Earthlikeness

Perspectives of Earth and Space Scientists, Volume 5, Issue 1, December 2024.
Abstract Standard notions of an “Earthlike” planet rely solely on physical and material properties, like planetary mass, radius, and surface temperature. Here, we introduce a novel, relational perspective on what defines “Earthlikeness.” In our process‐based framework, rocky planets are local pockets of free energy that have the potential to drive the ...
Michael L. Wong, Marissa Duckett, Emilia S. Hernandez, Vahab Rajaei, Kayla J. Smith   +4 more
wiley   +1 more source

A Gap in the Densities of Small Planets Orbiting M Dwarfs: Rigorous Statistical Confirmation Using the Open-source Code RhoPop

The Planetary Science Journal
Using mass–radius composition models, small planets ( R ≲ 2 R _⊕ ) are typically classified into three types: iron-rich, nominally Earth-like, and those with solid/liquid water and/or atmosphere.
J. G. Schulze, Ji Wang, J. A. Johnson, B. S. Gaudi, R. Rodriguez Martinez, C. T. Unterborn, W. R. Panero   +6 more
doaj   +1 more source

From Meteorite to Life's Building Blocks: A possible Electrochemical Pathway to Amino Acids and Peptide Bonds

Chemistry – A European Journal, Volume 30, Issue 57, October 11, 2024.
This study investigates the ability of the carbonaceous meteorite CV3 Allende to act as a catalyst in electrochemical interactions, triggering electrocatalytic reactions resulting in nitrogen (N2) fixation and conversion to ammonia. Additionally, the evolution of crucial compounds such as H2, CN− and sulfur/H2S was observed, along with the detection of
Lucas Fernandez, Farzaneh Yari, Günter Hesser, Wolfgang Schöfberger   +3 more
wiley   +1 more source