Results 21 to 30 of about 22,170 (245)
Maximum Angular Separation Epochs for Exoplanet Imaging Observations [PDF]
, 2018 Direct imaging of exoplanets presents both significant challenges and significant gains. The advantages primarily lie in receiving emitted and, with future instruments, reflected photons at phase angles not accessible by other techniques, enabling the ...
Kane, Stephen R. +2 more
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Commission No. 4: Ephemerides (Ephemerides) [PDF]
Transactions of the International Astronomical Union, 1988 It was the President’s sad duty to report the deaths of two former past Presidents of the Commission, W. Fricke who had also been a Vice-President of the IAU and a President of Commission 8, and D. H. Sadler who had been Superintendent of H.M. Nautical Almanac Office from 1936 to 1969 and was once General Secretary of the IAU.
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La propriété intellectuelle des calculs astronomiques en question
Philosophia Scientiæ, 2018 In 1885, the Bureau des longitudes (i.e., the French Board of longitude) had to adapt the ephemerides of the Connaissance des temps in order to answer the needs of the sailors.
Guy Boistel
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IEEE Access, 2023 BDS-3 was formally put into service on July 31, 2020, and now along with BDS-2 provides the positioning, navigation and timing services. In this contribution, different techniques of dual-frequency absolute positioning using the fully serviceable BDS-2 ...
Shengnan Liu, Shaolin Zhu, Jian Zhang
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Highlights of Astronomy, 1974 At the present time the planetary ephemerides in the Astronomical Ephemeris and in the American Ephemeris and Nautical Almanac (both hereinafter referred to as the AE), the Astronomical Ephemeris of the U.S.S.R. and most other national almanacs have the following basis: For Mercury, Venus, Earth, and Mars the general theories of Simon Newcomb (1898a ...
R. L. Duncombe +2 more
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Remote Sensing, 2021 Positioning accuracy is affected by the combined effect of user range errors and the geometric distribution of satellites. Dilution of precision (DOP) is defined as the geometric strength of visible satellites.
Haomeng Cui, Shoujian Zhang
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Orbital Period Refinement of CoRoT Planets with TESS Observations
Frontiers in Astronomy and Space Sciences, 2021 CoRoT was the first space mission dedicated to exoplanet detection. Operational between 2007 and 2012, this mission discovered 37 transiting planets, including CoRoT-7b, the first terrestrial exoplanet with a measured size. The precision of the published
Peter Klagyivik +8 more
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Transactions of the International Astronomical Union, 1982 The period of this Report includes 1984 January 1, the date which was probably the most drastic caesura in the history of astronomical almanacs. It seemed, therefore, appropriate to concentrate here to the general aspects rather than to describe the works going on at the particular almanac offices.
A M Sinzi +10 more
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Izračun položaja GPS-satelita iz podatkov oddanih efemerid : GPS-Orbit Computation from Broadcast Ephemeris Data [PDF]
Geodetski Vestnik, 2004 The article describes the theoretical point of view of the GPS-broadcast ephemerides application. Beside the raw GPS observations, any kind of GPS ephemerides represents indispensable data in the GPS processing engine.
Bojan Stopar +1 more
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What brakes the Crab pulsar? [PDF]
, 2015 Optical observations provide convincing evidence that the optical phase of the Crab pulsar follows the radio one closely. Since optical data do not depend on dispersion measure variations, they provide a robust and independent confirmation of the radio ...
Barbieri, C. +6 more
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