Results 51 to 60 of about 3,181,123 (208)

Inferring Io's Internal Properties by Combining Gravity Measurements and Volcanic Activity

Journal of Geophysical Research: Planets, Volume 131, Issue 9, September 2026.
Abstract With its extreme geological activity, Io represents an archetype for tidally heated exoplanets/moons and provides insight into early stages of terrestrial planet evolution. Decades of ground‐based observations and multiple space missions have refined our understanding of Io, yet it remains debated where inside Io the tidal heating takes place.
A. Veenstra, M. Rovira‐Navarro, W. van der Wal   +2 more
wiley   +1 more source

Direct Evidence of Photochemistry in an Exoplanet Atmosphere

, 2022
Photochemistry is a fundamental process of planetary atmospheres that is integral to habitability, atmospheric composition and stability, and aerosol formation. However, no unambiguous photochemical products have been detected in exoplanet atmospheres to
Aggarwal, Keshav, Cubillos, Patricio E., Line, Michael, Bean, Jacob L., Visscher, Channon, Alderson, Lili, Redfield, Seth, Gao, Peter, Baeyens, Robin, Crouzet, Nicolas, Behr, Patrick, Crossfield, Ian J. M., Schlawin, Everett, Lothringer, Joshua D., Grant, David, Fortney, Jonathan J., Hu, Renyu, Lopez-Morales, Mercedes, Yang, Jeehyun, France, Kevin, Daylan, Tansu, Bierson, Carver J., Wakeford, Hannah R, Tsai, Shang-Min, Powell, Diana, Carter, Aarynn L., Carone, Ludmila, Molaverdikhani, Karan, Yurchenko, Sergei N., Youngblood, Allison, Venot, Olivia, Kreidberg, Laura, Kirk, James, Brady, Ryan P., Moran, Sarah E., Berta-Thompson, Zachory K., Henning, Thomas, Taylor, Jake, Louca, Amy, Lendl, Monika, Decin, Leen, Moses, Julianne, Rustamkulov, Zafar, Wallack, Nicole L., Désert, Jean-Michel, Goyal, Jayesh M, Blecic, Jasmina, Mansfield, Megan, Miguel, Yamila, Welbanks, Luis, Batalha, Natalie M., Inglis, Julie, Mikal-Evans, Thomas, Wheatley, Peter J., Mukherjee, Sagnick, Batalha, Natasha E., Heng, Kevin, Leconte, Jérémy, Ohno, Kazumasa, Tremblin, Pascal, Rackham, Benjamin V., Krick, Jessica, Ahrer, Eva-Maria, Parmentier, Vivien, Jordan, Sean, Shorttle, Oliver, Barat, Saugata, Gibson, Neale P., Lee, Elspeth, Zhang, Xi, Harrington, Joseph, Mayne, N. J., Nasedkin, Evert, Alam, Munazza K., Palle, Enric, Borro, Miguel de Val, Casewell, S. L., Sing, David K., Stevenson, Kevin B., Feinstein, Adina D., Hébrard, Eric, Benneke, Björn, Kempton, Eliza M. -R., Lagage, Pierre-Olivier, Chubb, Katy L.   +84 more
core   +1 more source

Sub-Neptune Memories. I. Implications of Inefficient Mantle Cooling and Silicate Rain

The Astrophysical Journal
We explore the evolution of sub-Neptune (radii between ∼1.5 and 4 R _⊕ ) exoplanet interior structures using our upgraded evolution code, APPLE , which self-consistently couples the thermal and compositional evolution of the whole structure.
Roberto Tejada Arevalo, Akash Gupta, Adam Burrows, Donghao Zheng, Yao Tang, Jie Deng   +5 more
doaj   +1 more source

Outflowing Helium from a Mature Mini-Neptune

The Astrophysical Journal Letters, 2023
We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W _avg = 3.3 ± 0.3 mÅ.
Michael Zhang, Fei Dai, Jacob L. Bean, Heather A. Knutson, Federica Rescigno   +4 more
doaj   +1 more source

The Great Cosmic Silence: What Does the Fermi Paradox Tell About the Future of Humanity?

Global Policy, Volume 17, Issue 4, Page 553-565, September 2026.
ABSTRACT This article examines how institutional time horizons shape the long‐term survival prospects of human technological civilisation. While research on global catastrophic and existential risks has expanded, the temporal structures of political‐economic institutions remain underexamined.
Heikki Patomäki
wiley   +1 more source

Strong Fractionation of Deuterium and Helium in Sub-Neptune Atmospheres along the Radius Valley

The Astrophysical Journal
We simulate atmospheric fractionation in escaping planetary atmospheres using IsoFATE , a new open-source numerical model. We expand the parameter space studied previously to planets with tenuous atmospheres that exhibit the greatest helium and deuterium
Collin Cherubim, Robin Wordsworth, Renyu Hu, Evgenya Shkolnik   +3 more
doaj   +1 more source

The ORCA‐TWIN qCMOS Experiment I. Science Case and Commissioning at Calar Alto Observatory

Astronomische Nachrichten, Volume 347, Issue 7, August 2026.
ABSTRACT We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub‐electron readout noise.
Martin M. Roth, Paško Roje, Stella Vješnica, Stefan Cikota, Alex J. Brown, Mike Kretlow, Marco Azzaro, Santiago Reinhart, Jesús Aceituno, Harry Dawson, Carsten Denker, Torsten Enßlin, Stephan Geier, Thomas Granzer, Thomas Kupfer, Gianluca Li Causi, Samaya Nissanke, José Luis Ortiz, Fernando Pedichini, Katja Poppenhäger, Axel Schwope   +20 more
wiley   +1 more source

Helium Escape in Context: Comparative Signatures of Four Close-in Exoplanets

The Astrophysical Journal
Observations of escaping atmospheres on close-in exoplanets show a wide range in the strength and morphology of He I 10830 Å and H I absorption. Scaling relations attempt to link the He I signal to X-ray and UV irradiation, mass loss, and bulk planetary ...
Anna Ruth Taylor, Tommi T. Koskinen, Chenliang Huang, Anthony Arfaux, Panayotis Lavvas   +4 more
doaj   +1 more source

Massive Rocky Planets May Suppress Deep Melting

AGU Advances, Volume 7, Issue 4, August 2026.
Abstract Melting properties of silicates are critical to understanding the thermal evolution of rocky planetary interiors. In the deep mantles of massive rocky planets, post‐post‐spinel Mg2SiO4 ${\text{Mg}}_{2}{\text{SiO}}_{4}$ is potentially one of the most abundant mineral phases, yet its melting behavior remains unconstrained. Here, we determine the
Donghao Zheng, Yihang Peng, Jie Deng
wiley   +1 more source

Inverse modeling of European CH4 emissions: sensitivity to the observational network [PDF]

, 2009
Inverse modeling is widely employed to provide “top-down” emission estimates using atmospheric measurements. Here, we analyze the dependence of derived CH4 emissions on the sampling frequency and density of the observational surface network, using the ...
Bergamaschi, P., Villani, M.G., Sub Atmospheric physics and chemistry, Krol, M., Krol, M.C., Dep Natuurkunde, Dentener, F., Villani, M. G., Marine and Atmospheric Research, Meirink, J.F.   +9 more
core   +2 more sources