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Астронет: Астрономическая картинка дня Обратная сторона http://www.variable-stars.ru/db/msg/1161976/eng |
Credit & Copyright:
The Soviet Lunar Program
Explanation:
This historic picture was humanity's first glimpse of the far side of
the
Moon. It was taken by the Soviet spacecraft
Luna 3 in October of 1959. Luna 3 followed closely on the heels of
another Soviet probe, Luna 2,
which had become the
first spacecraft to impact the Moon
on September 13th of that same year.Why does the Moon have a far side? Gravitational tidal forces within the Earth-Moon system have synchronized the Moon's period of rotation around its axis with its orbital period at about 28 days. So, as the Moon moves around its orbit its rotation exactly compensates, keeping the same face toward the Earth.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.