Astronomical School’s Report, 2012, Volume 8, Issue 1, Pages 87–90

https://doi.org/10.18372/2411-6602.08.1087
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UDC 523.4

The reason for the difference data of photometric observations Galilean satellites from Earth and from space

Klianchin A.I.1, Prokof'eva-Mikchailovskaya V.V.2

1Main Astronomical Observatory NAS of Ukraine
2Crimean Astrophysical Observatory, Ukraine

Abstract

The four Galilean satellites of Jupiter have been studied with cosmic devices and from the Earth by astronomical means. Observations on board the spacecraft are usually obtained at large phase angles of the Sun. Observations from Earth are being done at phase angles of the Sun from 1 to 12 degrees. Large errors in the processing of the provisions satellite mutual phenomena occur because, in their treatment are used their light curves, which were obtained from the maps constructed from the spacecraft data. This can be explained only by the presence of bright spots on the surfaces of the eclipsed satellite, which leads to a different distribution of brightness across the disk of the satellite. About 30 years ago has been studied the inverse of coherent amplification of scattering. This phenomenon occurs in the regolith, covering the atmosphere-free bodies solar system. The presence of the inverse coherent scattering of the solar light at small phase angles of the Sun can explain the difference between the data of spacecraft observations and ground-based photometric measurements of the brightness of the Galilean satellites of Jupiter.

Keywords: regolith; phase angle

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