Soviet passive geodetic satellites; Etalon means "standard." Each
is spherical and covered with 306 antenna arrays, each array containing
14 corer cubes for laser reflection. Etalons were designed and launched
to enable the complete characterization of Earth's gravitational field at
the altitude and inclination planned for the Glonass navigation satellites.
They were also used to refine understanding of the Earth-Moon gravitational
system, to determine the effect of non-gravitational forces on satellites,
and for geophysical research. Only two Etalon satellites have been orbited,
each accompanied by a pair of GLONASS satellites.
Each was launched by a Proton rocket from
Baikonur, measured 1.3 × 1.3 m, and
had a mass of 1,415 kg.
||Jan. 10, 1989
||19,097 × 19,152 km × 64.9°
||May 31, 1989
||19,095 × 19,146 km × 65.5°
AND SPACE PROBES