Results 91 to 100 of about 6,726 (227)
Cahiers François Viète, 2016 The establishment of scientific education at the University of Coimbra was one of the most important features of the Pombal reform of the university (1772).
Fernando B. Figueiredo
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Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.Abstract We present conjugate observations of ionospheric small‐scale magnetic perturbations (dB) $(dB)$ and GPS scintillations from the Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) and the Canadian High Arctic Ionospheric Network (CHAIN) during a storm‐time substorm on 9 August 2025 in the nightside auroral region ...
Yangyang Shen +12 more
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Asteroid masses obtained with INPOP planetary ephemerides
Monthly notices of the Royal Astronomical Society, 2019 We present here masses of 103 asteroids deduced from their perturbations on theorbits of the inner planets, in particular Mars and the Earth. These determinations and theINPOP19a planetary ephemerides are improved by the recent Mars orbiter navigation ...
A. Fienga, C. Avdellidou, J. Hanus̆
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Electromagnetic Ion Cyclotron Waves in the Initial Phase of Geomagnetic Storms
Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.Abstract Using simultaneous magnetic field observations from 10 satellites and an automated detection algorithm, we identify broad regions of electromagnetic ion cyclotron (EMIC) wave activity during the initial phases of geomagnetic storms between September 2015 and October 2019.
Taylor R. Whitney Aegerter +1 more
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Izračun položaja GPS-satelita iz podatkov preciznih efimerid : GPS-orbit computation from precise ephemeris data [PDF]
Geodetski Vestnik, 2005 The article describes the theoretical point of view of the GPS precise ephemerides application that should be used in most precise GPS processing. Regarding broadcast, precise ephemerides allow us to achieve a much better accuracy of the final GPS ...
Bojan Stopar +1 more
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Material Property Sensitivity of Light Curve Attitude Estimation for the Lunar Trailblazer
Earth and Space Science, Volume 13, Issue 7, July 2026.Abstract The Lunar Trailblazer (LTB) spacecraft launched on 27 February 2025, toward a planned low‐lunar orbit. Eleven hours into its mission, contact with Trailblazer was lost, and recovery efforts began. Estimating the orientation and angular velocity state of Trailblazer was central for recovery to determine whether and when the vehicle could be ...
Liam Robinson +3 more
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Consistent tidal and rotational models for satellites in synchronous rotation
Astronomy & AstrophysicsTidal dissipation in natural satellites plays a crucial role in shaping their thermal state, internal structure, and evolution; for example, sustaining subsurface oceans in Europa and Enceladus and driving Io’s volcanic activity.
Magnanini Andrea +2 more
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Apophis source population and Earth encounter frequency of Apophis-like bodies
Astronomy & AstrophysicsContext. Asteroid (99942) Apophis will safely pass by the Earth in April 2029. This extraordinary event will be observable by the naked eye from Africa and western Europe. Aims.
Brož M. +6 more
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PERIOD CHANGE IN THE CONTACT SYSTEM AW UMA
Odessa Astronomical Publications, 2017 Nine new minima were determined from the UBV photoelectric observations obtained in 1992 and 1995-6. They were used to derive the new ephemerides of AW UMa. The mid-eclipse brightening best visible in U colour was detected.
T. Pribulla, D. Chochol
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A 16-parameter GEO Broadcast Ephemeris [PDF]
Journal of Geodesy and Geoinformation Science, 2018 Currently, the broadcast ephemerides used in GEOs are same as those of the MEOs and IGSOs in the BeiDou navigation constellation. However, a trade-off strategy, i.e.
Zhongkai ZHANG,Lan DU,Li LIU,Feng HE,Yu LU,Peiyuan ZHOU
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