Tootfinder

Can a convecting magma ocean offer a solution to the puzzling case of core convection in early earth?
Urmi Dutta, Chris J. Davies, Ashley P. Willis
https://arxiv.org/abs/2507.22521

Can a convecting magma ocean offer a solution to the puzzling case of core convection in early earth?
Convective flow in Earth's iron-rich liquid core drives self-sustained dynamo action, generating Earth's magnetic field, which is strongest among all terrestrial planets of the solar system. Rock records show that this magnetic field has been operative in Earth for at least 3.4 billion years (b.y). However, advanced high pressure experiments have revised the value of the thermal conductivity of the outer core, which implies an age for the inner core of less than 1 b.y., when compositional conve…

I haven't watched "Alien: Earth" yet except for a youtube video that decries bad writing. But I know that spaceship crash sequence. And this made me think: why do spaceships (not just this one) crash like airplanes instead of ramming straight into the ground? If it's an out of control vessel then the low angle of approach only makes sense if its trajectory is grazing earth (almost missing it).
Is that the case here? But why its belly oriented towards the ground then an…

Accurate calculation of light rare-earth magnetic anisotropy with density functional theory
Liqin Ke, R. Flint, Y. Lee
https://arxiv.org/abs/2508.19496 https://

Accurate calculation of light rare-earth magnetic anisotropy with density functional theory
Density functional theory (DFT) has long struggled to treat light rare-earth magnetism. We show that this difficulty arises from an overestimate of the $4f$ charge asphericity, and thus the magnetic anisotropy energy, due to the inadequacy of single Slater-determinant representations. We propose an effective solution by combining constrained DFT+U with crystal field theory and a systematic many-body correction to the charge asphericity. We confirm the validity of this combination on TbV$_6$Sn$_…

Earthquake body wave extraction using sparsity-promoting polarization filtering in the time-frequency domain
Hamzeh Mohammadigheymasi, Bahare Imanibadrbani, Ali Gholami, Ahmad Sadidkhouy
https://arxiv.org/abs/2508.20542

Earthquake body wave extraction using sparsity-promoting polarization filtering in the time-frequency domain
Seismic waves generated by earthquakes consist of multiple phases that carry critical information about Earth's internal structure as they propagate through heterogeneous media. These phases provide constraints from different regions of the Earth, such as the crust, mantle, and even the cores. The choice of phase depends on the study target and scientific objective: surface waves are suited for imaging shallow structures, whereas body waves yield higher-resolution information at depth. A key ch…

Efficient ion re-acceleration in laboratory-produced interpenetrating collisionless shocks
W. Yao, I. Cohen, P. Suarez Gerona, H. Ahmed, A. F. A. Bott, S. N. Chen, M. Cook, R. Leli\`evre, P. Martin, T. Waltenspiel, P. Antici, J. B\'eard, M. Borghesi, D. Caprioli, A. Ciardi, E. d'Humi\`eres, M. Fran\c{c}ois, L. Gremillet, A. Marcowith, M. Miceli, T. Seebaruth, S. Orlando, J. Fuchs

Efficient ion re-acceleration in laboratory-produced interpenetrating collisionless shocks
Although the origin of cosmic rays (CRs) remains an open question, collisionless magnetized shock waves are widely regarded as key sites for particle acceleration. Recent theories further suggest that shock-shock collisions in stellar clusters could provide the additional acceleration needed to explain the observed high-energy CR spectrum. Here, we investigate this hypothesis through a laser-based experiment that creates magnetized plasma conditions similar to astrophysical environments. Our re…

Sustainability or Survivability? Eliminating the Need to Choose in LEO Satellite Constellations
Chris Misa, Ramakrishnan Durairajan
https://arxiv.org/abs/2508.17763 https://

Sustainability or Survivability? Eliminating the Need to Choose in LEO Satellite Constellations
LEO Satellite Networks (LSNs) are revolutionizing global connectivity, but their reliance on tens of thousands of satellites raises pressing concerns over sustainability and survivability. In this work, we argue that the inefficiencies in LSN designs stem from ignoring the strong spatiotemporal structure of Internet traffic demand (which impacts sustainability) and the physical realities of the near-Earth space environment (which affects survivability). We propose a novel design approach based …

An optical-lensing inspired data thinning method for nuclear cross section data
M. Imbri\v{s}ak, A. E. Lovell, M. R. Mumpower
https://arxiv.org/abs/2508.19470 https://

An optical-lensing inspired data thinning method for nuclear cross section data
In the study of nuclear cross sections, the computational demands of data assimilation methods can become prohibitive when dealing with large data sets. We have developed a novel variant of the data thinning algorithm, inspired by the principles of optical lensing, which effectively reduces data volume while preserving critical information. We show how it improves fitting through a toy problem and for several examples of total cross sections for neutron-induced reactions on rare-earth isotopes.…

One year of ASPEX-SWIS operation -- Characteristic features, observations and science potential
Abhishek Kumar, Shivam Parashar, Prashant Kumar, Dibyendu Chakrabarty, Bhas Bapat, Aveek Sarkar, Manan S. Shah, Hiteshkumar L. Adalja, Arpit R. Patel, Pranav R. Adhyaru, M. Shanmugam, Swaroop B. Banerjee, K. P. Subramaniam, Tinkal Ladiya, Jacob Sebastian, Bijoy Dalal, Aakash Gupta, M. B. Dadhania, Santosh V. Vadawale, Shiv Kumar Goyal, Neeraj Kumar Tiwari, Aaditya Sarda, Sushil Kumar, Nishan…

One year of ASPEX-SWIS operation -- Characteristic features, observations and science potential
The Aditya-L1 mission, India's first dedicated solar observatory positioned at the first Lagrange point (L1) of the Sun-Earth system, carries the Solar Wind Ion Spectrometer (SWIS) as part of the ASPEX payload suite. Even before settling into its Halo orbit, SWIS has been providing nearly continuous in-situ measurements of solar wind ion spectra. Moments of the velocity distribution functions (VDFs) have been calculated to derive key solar wind parameters such as density, bulk speed, and temper…

The political neutral Red Cross about the situation in Gaza.
"Gaza worse than hell on Earth"
https://www.bbc.com/news/live/cvg5vyp33j1t?post=asset:09e08599-9e3d-4878-a965-ff0fd0054fe1#post

Gaza worse than hell on Earth, Red Cross chief tells BBC as aid centres close for day
The president of the ICRC tells the BBC's international editor Jeremy Bowen Palestinians have been stripped of human dignity.

Modeling Orbital Decay of Low-Earth Orbit Satellites due to Atmospheric Drag: A Simplified Analytical Approach
Sukdev Mahapatra
https://arxiv.org/abs/2508.19549 https://

Modeling Orbital Decay of Low-Earth Orbit Satellites due to Atmospheric Drag: A Simplified Analytical Approach
Low-Earth Orbit (LEO) satellites are crucial for communications, navigation, and Earth observation. However, their operational lifetimes are strongly influenced by orbital decay due to atmospheric drag. This work presents a simplified analytical model of orbital decay in LEO, incorporating atmospheric density variations and satellite parameters. Using standard drag force equations and density models, we explore how altitude, satellite mass, and cross-sectional area affect decay timescales. Comp…