Results 21 to 30 of about 10,991 (143)

Advancing Our Understanding of Martian Proton Aurora Through a Coordinated Multi‐Model Comparison Campaign

Journal of Geophysical Research: Space Physics, Volume 128, Issue 10, October 2023., 2023
Abstract Proton aurora are the most commonly observed yet least studied type of aurora at Mars. In order to better understand the physics and driving processes of Martian proton aurora, we undertake a multi‐model comparison campaign. We compare results from four different proton/hydrogen precipitation models with unique abilities to represent Martian ...
Andréa C. G. Hughes, Michael Chaffin, Edwin Mierkiewicz, Justin Deighan, Rebecca D. Jolitz, Esa Kallio, Guillaume Gronoff, Valery Shematovich, Dmitry Bisikalo, Jasper Halekas, Cyril Simon Wedlund, Nicholas Schneider, Birgit Ritter, Zachary Girazian, Sonal Jain, Jean‐Claude Gérard, Bradley Hegyi   +16 more
wiley   +1 more source

Ultrahigh‐Pressure Acoustic Velocities of Aluminous Silicate Glass up to 155 GPa With Implications for the Structure and Dynamics of the Deep Terrestrial Magma Ocean

Geophysical Research Letters, Volume 50, Issue 14, 28 July 2023., 2023
Abstract We have carried out in situ high‐pressure acoustic velocity measurements of (Fe2+, Al)‐bearing MgSiO3 glass up to pressures of 155 GPa, which confirmed a distinct pressure‐induced trend change in the transverse acoustic velocity (VS) profile around 98 GPa, likely caused by the Si‐O coordination number (CN) change from 6 to 6+.
Pinku Saha, Motohiko Murakami, Catherine McCammon, Christian Liebske, Ewa Krymarys   +4 more
wiley   +1 more source

Is There a Semi‐Molten Layer at the Base of the Lunar Mantle?

Journal of Geophysical Research: Planets, Volume 128, Issue 7, July 2023., 2023
Abstract Parameterised by the Love number k2 and the tidal quality factor Q, and inferred from lunar laser ranging (LLR), tidal dissipation in the Moon follows an unexpected frequency dependence often interpreted as evidence for a highly dissipative, melt‐bearing layer encompassing the core‐mantle boundary.
Michaela Walterová, Marie Běhounková, Michael Efroimsky   +2 more
wiley   +1 more source

Groundwater Microbiology of an Urban Open‐Loop Ground Source Heat Pump with High Methane

Groundwater, Volume 61, Issue 2, Page 274-287, March/April 2023., 2023
Abstract Ground source heat pumps (GSHPs) are low‐carbon alternatives to gas boilers for decarbonizing heating. Open‐loop GSHP systems abstract groundwater, pass it through a heat exchanger, and return it to ground or surface water. Groundwater samples from the top and base of an abstraction and a recharge borehole of an open‐loop GSHP system in ...
Megan J. Barnett, Gareth J. Farr, Jianxun Shen, Simon Gregory   +3 more
wiley   +1 more source

Penetrative Superplumes in the Mantle of Large Super‐Earth Planets: A Possible Mechanism for Active Tectonics in the Massive Super‐Earths

Geochemistry, Geophysics, Geosystems, Volume 24, Issue 2, February 2023., 2023
Abstract Recent theoretical studies suggest that the physical and rheological mantle properties in massive rocky planets fall outside conventional behaviors inferred for mantle properties at the Earth's mantle pressures. The vacancy diffusion occurring at low pressures is assumed to be followed by interstitial diffusion above ∼0.1 TPa resulting in ...
M. H. Shahnas, R. N. Pysklywec
wiley   +1 more source

MHD Study of Extreme Space Weather Conditions for Exoplanets With Earth‐Like Magnetospheres: On Habitability Conditions and Radio‐Emission

Space Weather, Volume 20, Issue 11, November 2022., 2022
Abstract The present study aims at characterizing the habitability conditions of exoplanets with an Earth‐like magnetosphere inside the habitable zone of M and F stars, caused by the direct deposition of the stellar wind on the exoplanet surface.
J. Varela, A. S. Brun, P. Zarka, A. Strugarek, F. Pantellini, V. Réville   +5 more
wiley   +1 more source

X‐ray irradiation of three planets around Hyades star K2‐136

Astronomische Nachrichten, Volume 343, Issue 4, May 2022., 2022
Abstract We study the X‐ray irradiation and likely photoevaporation of the three planets around the star K2‐136. These are the Earth‐sized K2‐136 b, the mini‐Neptune K2‐136 c, and the super‐Earth K2‐136 d. XMM‐Newton observations of the star indicate an X‐ray luminosity of in the range 0.15–2.4 keV, resulting in an activity of . The evaporation past of
Jorge Fernández Fernández, Peter J. Wheatley   +1 more
wiley   +1 more source

Self-consistent Spin, Tidal, and Dynamical Equations of Motion in the REBOUNDx Framework

The Astrophysical Journal, 2023
We introduce self-consistent spin, tidal, and dynamical equations of motion into REBOUNDx , a library of additional effects for the popular N -body integrator REBOUND .
Tiger Lu, Hanno Rein, Daniel Tamayo, Sam Hadden, Rosemary Mardling, Sarah C. Millholland, Gregory Laughlin   +6 more
doaj   +1 more source

Planet-Planet Tides in the TRAPPIST-1 System [PDF]

Res. Notes AAS, 2, 175, 2018
The star TRAPPIST-1 hosts a system of seven transiting, terrestrial exoplanets apparently in a resonant chain, at least some of which are in or near the Habitable Zone. Many have examined the roles of tides in this system, as tidal dissipation of the orbital energy of the planets may be relevant to both the rotational and orbital dynamics of the ...
arxiv   +1 more source

High-eccentricity Migration with Disk-induced Spin–Orbit Misalignment: A Preference for Perpendicular Hot Jupiters

The Astrophysical Journal Letters, 2023
High-eccentricity migration is a likely formation mechanism for many observed hot Jupiters, particularly those with a large misalignment between the stellar spin axis and orbital angular momentum axis of the planet.
Michelle Vick, Yubo Su, Dong Lai
doaj   +1 more source