Results 1 to 10 of about 5,627 (172)
Testing Theories of Gravity With Planetary Ephemerides [PDF]
Living Reviews in Relativity, 2023 We describe here how planetary ephemerides are built in the framework of General Relativity and how they can be used to test alternative theories. We focus on the definition of the reference frame (space and time) in which the planetary ephemeris is ...
Olivier Minazzoli, Agnes Fienga
exaly +3 more sources
ASSESSING EFFICIENCY OF GPS EPHEMERIDES IN DIFFERENT REGION USING PRECISE POINT POSITIONING [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2023 Precise Point Positioning (PPP) is a technique that process Global Positioning System (GPS) observation that can achieve sub-decimetre accuracy. Precise ephemerides that contain satellite clock and position plays a vital role in minimising orbital and ...
H. S. Lee +3 more
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Newly found Mayan records of astronomical phenomena in Dresden Codex [PDF]
Serbian Astronomical Journal, 2023 The rich culture of old Maya gave birth to a very complicated and complex calendar; they also recorded important historical events and many significant astronomical phenomena.
Vondrák J., Böhm V., Böhm B.
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AGG+, 2021 This paper analyses how broadcast and precise ephemerides in alignment, using the least-squares method, affect the accuracy of coordinates of the newly included permanent stations.
Tanja Đukanović +2 more
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Effect of using different satellite ephemerides on GPS PPP and post processing techniques
Geodesy and Cartography, 2021 The orbital error is one of the errors in GPS which affect the accuracy of GPS positioning. In this research GPS broadcast, ultra-rapid, rapid and precise satellite ephemerides are used for processing different baseline lengths among some CORS stations ...
Khaled Mahmoud Abdel Aziz +1 more
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Did old Maya observe Mercury? [PDF]
Serbian Astronomical Journal, 2022 It is well known that the rich culture of old Maya contained, among other, also a very complicated and complex calendar, in which they recorded not only historical events, but also significant astronomical phenomena.
Vondrák J., Böhm V., Böhm B.
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Implementation of the variation of the luni-solar acceleration into GLONASS orbit calculus [PDF]
Geodetski Vestnik, 2021 In the differential equation system describes the motion of GLONASS satellites (rus. Globalnaya Navigazionnaya Sputnikovaya Sistema, or Global Navigation Satellite System ), the acceleration caused by the luni-solar traction is often taken as a constant ...
Sid Ahmed Medjahed +3 more
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Orbital Elements Ephemerides and Interfaces Design of LEO Satellites [PDF]
Journal of Geodesy and Geoinformation Science, 2019 Low earth orbit satellites, with unique advantages, are prosperous types of navigation augmentation satellites for the GNSS satellites constellations. The broadcast ephemeris element needs to be designed as an important index of the augmented LEOs.
Shanchuan FANG,Lan DU,Yunpeng GAO,Peiyuan ZHOU,Zejun LIU
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Astronomical phenomena in Dresden codex [PDF]
Serbian Astronomical Journal, 2013 The relationship between Maya and our calendar is expressed by a coefficient known as ‘correlation’ which is a number of days that we have to add to the Mayan Long Count date to get Julian Date used in astronomy.
Böhm V. +4 more
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Revisiting the 2PN Pericenter Precession in View of Possible Future Measurements
Universe, 2020 At the second post-Newtonian (2PN) order, the secular pericenter precession ω ˙ 2 PN of either a full two-body system made of well-detached non-rotating monopole masses of comparable size and a restricted two-body system composed of a point
Lorenzo Iorio
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