Direct measurements of laser light scattering and aberration from the ARTEMIS geostationary satellite through thin clouds
Abstract
A precise ground based telescope system was developed for laser communication experiments with the geostationary satellite ARTEMIS of ESA. Precise tracking of the satellite was realized by using time resolved coordinates of the satellite. During the experiments, the time propagation of laser signal from the satellite and the point-ahead angle for the laser beam was calculated. Some laser experiments though thin clouds were performed. A splitting of some images of the laser beam from the satellite along declination and right ascension coordinates of telescope could be observed through thin clouds. The splitting along the declination coordinate may be interpreted as Raman scattering on molecules of water and strong refraction at small angles over horizon in the atmosphere. The splitting along the right ascension coordinate is equivalent to the calculated point-ahead angle for the satellite. We find out that a small part of laser beam was observed ahead of the velocity vector in the point where the satellite would be after the laser light from the satellite reaches the telescope. These results are in accordance with the theory of relativity for aberration of light during transition from immovable to movable coordinate systems. The stellar aberration, as a result of the Earth motion around of the Sun, was discovered by James Bradley in 1727 year performing observation positions of stars during the year. These results are in accordance with the theory of relativity also. We directly observed laser light aberration as result of moving of geostationary satellite with velocity 3.07 km/s in direction of Earth rotation. By using same methodical we directly observed light aberration of two stars also. We think that this methodical open way for direct determine of light aberration for different objects in our galactic also.
- Publication:
-
Astronomy and space physics at Kyiv university. International conference
- Pub Date:
- May 2017
- Bibcode:
- 2017aspk.conf...35K
- Keywords:
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- laser light;
- aberration;
- geostationary satellite;
- the theory of relativity