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Related papers: A frequency portrait of Low Earth Orbits

200 papers

We present a formalism for computing time-dependent fluctuations in the cosmological photoionizing radiation background, extending background fluctuations models beyond the steady-state approximation. We apply this formalism to estimate…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-01 Avery Meiksin , Matthew McQuinn

Reflections from objects in Earth orbit can produce sub-second, star-like optical flashes similar to astrophysical transients. Reflections have historically caused false alarms for transient surveys, but the population has not been…

Low earth orbit (LEO) satellite navigation signal can be used as an opportunity signal in case of a Global navigation satellite system (GNSS) outage, or as an enhancement means of traditional GNSS positioning algorithms. No matter which…

Signal Processing · Electrical Eng. & Systems 2021-06-01 Liang Chen , Xiangchen Lu , Nan Shen , Lei Wang , Yuan Zhuang , Ye Su , Deren Li , Ruizhi Chen

The magnetic and convective nature of the Sun's photosphere provides a unique platform from which generated waves can be modelled, observed, and interpreted across a wide breadth of spatial and temporal scales. As oscillations are generated…

Solar and Stellar Astrophysics · Physics 2020-12-01 David B. Jess , Peter H. Keys , Marco Stangalini , Shahin Jafarzadeh

The increasing frequency and severity of climate related disasters have intensified the need for real time monitoring, early warning, and informed decision-making. Earth Observation (EO), powered by satellite data and Machine Learning (ML),…

Computer Vision and Pattern Recognition · Computer Science 2026-05-12 Stella Girtsou , Konstantinos Alexis , Giorgos Giannopoulos , Charalambos Kontoes

The next frontier towards truly ubiquitous connectivity is the use of Low Earth Orbit (LEO) small-satellite constellations to support 5G and Beyond-5G (B5G) networks. Besides enhanced mobile broadband (eMBB) and massive machine-type…

Networking and Internet Architecture · Computer Science 2020-10-08 Israel Leyva-Mayorga , Beatriz Soret , Maik Röper , Dirk Wübben , Bho Matthiesen , Armin Dekorsy , Petar Popovski

Low earth orbit (LEO) satellite has been considered as a potential supplement for the terrestrial Internet of Things (IoT). In this paper, we consider grant-free non-orthogonal random access (GF-NORA) in orthogonal frequency division…

Signal Processing · Electrical Eng. & Systems 2022-11-01 Yong Zuo , Mingyang Yue , Mingchen Zhang , Sixian Li , Shaojie Ni , Xiaojun Yuan

Radio-loud active galactic nuclei (RLAGN) play an important role in the evolution of galaxies through the effects on their environment. The two major morphological classes are core-bright (FRI) and edge-bright (FRII) sources. With the…

This study presents the first global analysis of on-demand video streaming over Low Earth Orbit (LEO) satellite networks, using data from over one million households across 85 countries. We highlight Starlink's role as a major LEO provider,…

Networking and Internet Architecture · Computer Science 2024-09-17 Liz Izhikevich , Reese Enghardt , Te-Yuan Huang , Renata Teixeira

Using long-duration observations in the He II 304 Angstrom passband of the Solar and Heliospheric Observatory (SOHO) Extreme-ultraviolet Imaging Telescope (EIT) we investigate the spatial and temporal appearance of impulsive intensity…

Astrophysics · Physics 2009-01-19 Scott W. McIntosh

Using a Bayesian framework, we quantify what current observations imply about the history of the epoch of reionisation (EoR). We use a popular, three-parameter EoR model, flexible enough to accommodate a wide range of physically-plausible…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-01 Bradley Greig , Andrei Mesinger

We review the expected science performance of the New Gravitational-Wave Observatory (NGO, a.k.a. eLISA), a mission under study by the European Space Agency for launch in the early 2020s. eLISA will survey the low-frequency…

We numerically investigate the dynamics of rotation of several close-in terrestrial exoplanet candidates. In our model, the rotation of the planet is disturbed by the torque of the central star due to the asymmetric equilibrium figure of…

Earth and Planetary Astrophysics · Physics 2015-06-05 Nelson Callegari , Adrian Rodríguez

Following the report of solar-like oscillations in the G0 V star eta Boo (Kjeldsen et al. 1995, AJ 109, 1313), a first attempt to model the observed frequencies was made by Christensen-Dalsgaard et al. (1995, ApJ Letters, in press). This…

The interaction of backstreaming ions with the incoming solar wind in the upstream region of the bow shock gives rise to a number of plasma instabilities from which ultra-low frequency (ULF) waves can grow. Because of their finite growth…

Space Physics · Physics 2015-08-06 Nahuel Andres , Karim Meziane , Christian Mazelle , Cesar Bertucci , Daniel Gomez

Eccentric ellipsoidal variables (aka heartbeat stars) is a class of eccentric binaries in which proximity effects, tidal distortion due to time-dependent tidal potential in particular, lead to measurable photometric variability close to the…

Solar and Stellar Astrophysics · Physics 2022-03-14 P. A. Kołaczek-Szymański , A. Pigulski , M. Wrona , M. Ratajczak , A. Udalski

We examine the effects of a periodically varying flow velocity on the standing and travelling wave patterns formed by the flow-distributed oscillation (FDO) mechanism. In the kinematic (or diffusionless) limit, the phase fronts undergo a…

Pattern Formation and Solitons · Physics 2009-11-11 Patrick N. McGraw , Michael Menzinger

The coming extension of cellular technology to base-stations in low-earth orbit (LEO) requires a fresh look at terrestrial 3GPP channel models. Relative to such models, sky-to-ground cellular channels will exhibit less diffraction, deeper…

Signal Processing · Electrical Eng. & Systems 2021-07-30 Eunsun Kim , Ian P. Roberts , Peter A. Iannucci , Jeffrey G. Andrews

We analyze all available RXTE data on a sample of 13 low mass X-ray binaries with known neutron star spin that are not persistent pulsars. We carefully measure the correlations between the centroid frequencies of the quasi-periodic…

High Energy Astrophysical Phenomena · Physics 2016-11-18 Marieke van Doesburgh , Michiel van der Klis

The emission from neutral hydrogen (HI) clouds in the post-reionization era (z < 6), too faint to be individually detected, is present as a diffuse background in all low frequency radio observations below 1420 MHz. The angular and frequency…

Astrophysics · Physics 2009-10-29 Somnath Bharadwaj , Shiv K. Sethi , Tarun Deep Saini