Results 71 to 80 of about 26,344 (179)

Jupiter’s Interior with an Inverted Helium Gradient

The Planetary Science Journal
Jupiter’s gravity field observed by NASA’s Juno spacecraft indicates that the density in the 10–100 GPa region is lower than one would expect from a H/He adiabat with 0.5–5× solar water abundance, as has been observationally inferred in Jupiter’s ...
N. Nettelmann, J. J. Fortney
doaj   +1 more source

Scientific Value of a Saturn Atmospheric Probe Mission [PDF]

, 2012
Atmospheric entry probe mISSions to the giant planets can uniquely discriminate between competing theories of solar system formation and the origin and evolution of the giant planets and their atmospheres.
Atkinson, D. H., Atreya, S. K., Coustenis, A., Lunine, J. I., Simon-Miller, A. A., Spilker, T. R.   +5 more
core   +1 more source

Climate Emergency and Different Ways to Fail? The Fermi Paradox, the Simulation Hypothesis, Agency and Hope

Journal for the Theory of Social Behaviour, Volume 55, Issue 4, December 2025.
ABSTRACT Humanity seems stuck on different ways to fail to meet the challenge posed by a declared climate emergency and manifest problems of ecological breakdown. Rather than reprise these failures, we use the Fermi Paradox and simulation hypothesis to make a simple point about agency. The argument unfolds in two sections.
Jamie Morgan
wiley   +1 more source

Phase Engineering of Cobalt‐Based Perovskite Oxides Toward Enhanced Oxygen Evolution Electrocatalysis

ChemElectroChem, Volume 12, Issue 22, November 5, 2025.
Water electrolysis offers a sustainable hydrogen production route, yet the kinetics for the anodic oxygen evolution reaction (OER) remain sluggish. Phase engineering via thermal reduction transforms hexagonal perovskite cobaltites into cubic structures, increasing oxygen vacancies and reducing cobalt valence.
Xiaomin Xu, Chun‐Kuo Peng, Yan‐Gu Lin, Zongping Shao   +3 more
wiley   +1 more source

Temperatures of Jupiter’s Upper Atmosphere: The Role of the Planetary Magnetic Field

The Astrophysical Journal Letters
The primary source of heating in the upper atmospheres (thermospheres) of giant planets has been the subject of long debate. The conundrum (or “energy crisis”) consists in observed thermosphere temperatures at low and midlatitudes exceeding values ...
Ingo C. F. Müller-Wodarg, Peio Iñurrigarro, Luke Moore, Tommi T. Koskinen, Alexander S. Medvedev   +4 more
doaj   +1 more source

Atmospheric Circulation of Exoplanets [PDF]

, 2009
We survey the basic principles of atmospheric dynamics relevant to explaining existing and future observations of exoplanets, both gas giant and terrestrial.
Cho, James Y-K., Menou, Kristen, Showman, Adam P.   +2 more
core   +1 more source

Pervasive Orbital Eccentricities Dictate the Habitability of Extrasolar Earths

, 2010
The long-term habitability of Earth-like planets requires low orbital eccentricities. A secular perturbation from a distant stellar companion is a very important mechanism in exciting planetary eccentricities, as many of the extrasolar planetary systems ...
Kita, Ryosuke, Rasio, Frederic A., Takeda, Genya   +2 more
core   +1 more source

Do we expect to find the Super-Earths close to the gas giants?

, 2009
We have investigated the evolution of a pair of interacting planets embedded in a gaseous disc, considering the possibility of the resonant capture of a Super-Earth by a Jupiter mass gas giant.
Armitage, E. Podlewska, Fogg, Fogg, Lecar, Masset, Nelson, Papaloizou, Pierens, Podlewska, Podlewska, Raymond, Raymond, Udry, Winter   +14 more
core   +1 more source

Equations of State, Thermodynamics, and Miscibility Curves for Jovian Planet and Giant Exoplanet Evolutionary Models

The Astrophysical Journal Supplement Series
The equation of state of hydrogen–helium (H–He) mixtures plays a vital role in the evolution and structure of gas giant planets and exoplanets. Recent equations of state that account for H–He interactions, coupled with H–He immiscibility curves, can now ...
Roberto Tejada Arevalo, Yubo Su, Ankan Sur, Adam Burrows   +3 more
doaj   +1 more source

Microlensing Results Challenge the Core Accretion Runaway Growth Scenario for Gas Giants

, 2018
We compare the planet-to-star mass-ratio distribution measured by gravitational microlensing to core accretion theory predictions from population synthesis models.
Alibert, Yann, Bennett, David P., Bhattacharya, Aparna, Bond, Ian A., Donachie, Martin, Fukui, Akihiko, Hirao, Yuki, Ida, Shigeru, Koshimoto, Naoki, Lin, Douglas N. C., Miyazaki, Shota, Mordasini, Christoph, Nagakane, Masayuki, Ranc, Clément, Rattenbury, Nicholas J., Sumi, Takahiro, Suzuki, Daisuke   +16 more
core   +1 more source