ADDRESS: The utilization of artificial earth satellites for astronomical research

1959 ◽  
Vol 64 ◽  
pp. 45 ◽  
Author(s):  
L. H. Aller
1991 ◽  
Vol 112 ◽  
pp. 115-125
Author(s):  
Paul D. Maley

Astronomical research continues to use ground-based facilities as a principal means of gathering data. The optical light buckets which are trained each night on celestial sources have historically had to just contend with natural interference. Sunlight, moonlight, clouds, debris created by volcanic eruptions, atmospheric seeing, and aurora are examples of factors which modify the interception and analysis of energy radiated in the optical spectrum and received at the collector end. In the last 5 years the “unnatural” encounters with artificial earth satellites are making themselves more pronounced and have become the subject of this limited study.


2001 ◽  
Vol 24 (3) ◽  
pp. 187-196
Author(s):  
Pulat B. Babadzhanov

AbstractAstronomical researches in Tajikistan are carried out by the Institute of Astrophysics, Tajik Academy of Sciences. The main scientific fields of investigation are physics and dynamics of asteroids, comets and meteors, variable stars and observations of artificial Earth satellites. The Institute has three observational stations: the Gissar observatory (at an altitude 730 m above sea-level) with photographic fireball and meteor patrols, a 70-cm reflector, a 40-cm Zeiss astrograph, a high-precision astronomical telescope (D=1 m, F=0.75 m), etc.; the Sanglokh observatory (at an altitude 2300 m above sea-level) with a Ritchey-Chretien 1-m telescope and 0.6-m reflector by Carl Zeiss; the Pamir observatory (at an altitude 4350 m above sea-level) with a 70-cm reflector. In 1999 the Department of Astronomy was restored in the Tajik State National University and the first students were admitted to this university for the astronomical profession.


Author(s):  
М. В. Братійчук ◽  
А. Г. Кириченко ◽  
В. П. Єпішев

2021 ◽  
Vol 133 (4) ◽  
Author(s):  
K. Sośnica ◽  
G. Bury ◽  
R. Zajdel ◽  
K. Kazmierski ◽  
J. Ventura-Traveset ◽  
...  

AbstractThe first pair of satellites belonging to the European Global Navigation Satellite System (GNSS)—Galileo—has been accidentally launched into highly eccentric, instead of circular, orbits. The final height of these two satellites varies between 17,180 and 26,020 km, making these satellites very suitable for the verification of the effects emerging from general relativity. We employ the post-Newtonian parameterization (PPN) for describing the perturbations acting on Keplerian orbit parameters of artificial Earth satellites caused by the Schwarzschild, Lense–Thirring, and de Sitter general relativity effects. The values emerging from PPN numerical simulations are compared with the approximations based on the Gaussian perturbations for the temporal variations of the Keplerian elements of Galileo satellites in nominal, near-circular orbits, as well as in the highly elliptical orbits. We discuss what kinds of perturbations are detectable using the current accuracy of precise orbit determination of artificial Earth satellites, including the expected secular and periodic variations, as well as the constant offsets of Keplerian parameters. We found that not only secular but also periodic variations of orbit parameters caused by general relativity effects exceed the value of 1 cm within 24 h; thus, they should be fully detectable using the current GNSS precise orbit determination methods. Many of the 1-PPN effects are detectable using the Galileo satellite system, but the Lense–Thirring effect is not.


1994 ◽  
Vol 49 (4) ◽  
pp. 1693-1706 ◽  
Author(s):  
Thibault Damour ◽  
Gilles Esposito-Farèse

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