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Voyager spacecraft
The Voyager 1 spacecraft is an unmanned probe of the outer solar system, originally planned as Mariner 11 of the Mariner program. It was launched on September 5,
1977 by NASA from Cape Canaveral aboard a Titan-Centaur rocket, slightly after its
sister craft, Voyager 2, in an orbit that caused it to reach Jupiter first. The two Voyager program spacecrafts are identical.
Jupiter and Saturn
Voyager 1 began photographing Jupiter in January 1979. Its closest approach to Jupiter was on March 5, 1979, and it finished photographing the planet in April.
The two Voyager spacecraft made a number of important discoveries about Jupiter and its satellites. The most surprising was
the existence of sulfur volcanoes on
Io, which had not been observed from the ground or by Pioneer 10 or 11.
The spacecraft went on to visit Saturn. Voyager 1's Saturn
flyby occurred in November 1980, with the closest approach on November 12 when it came within 77,000 miles of the planet's cloud-tops. The craft detected complex
structures in Saturn's rings, and studied the atmospheres of Saturn and Titan. Its orbit, designed to allow close study of Titan, took it out of the plane of the ecliptic, thus
ending its planetary science mission.
Heliopause
As it heads for interstellar space, its instruments continue to study the solar system; Jet
Propulsion Laboratory scientists are using the plasma wave experiments aboard Voyager 1 and 2 to look for the heliopause. It was announced by NASA on Wednesday
November 5, 2003 (that day Voyager 1
reached a distance of 90 AU from sun) that scientists at the
Johns Hopkins University Applied Physics Lab
believe that Voyager passed the termination shock in February
2003. However some other scientists have expressed doubt (discussed in the journal
Nature of November 6). The issue will not be resolved for some months
as other data becomes available, since Voyager's solar-wind detector ceased functioning in 1990.
Voyager 1 is expected to keep on transmitting into the 2020s.
Distance Travelled
As of January 2004, Voyager 1 was at a distance of 13.5 billion kilometers (90.5 Astronomical Units, 8.4 billion miles or 12.5 light-hours) from the Sun. Voyager 1 is escaping
the solar system at a speed of about 3.6 AU (19 light-minutes) per year (ca. 17 km/s).
Golden Record
Voyager Golden Record Protective Cover
Voyager 1 carries with it a golden record (Voyager Golden
Record) that contains pictures and sounds of Earth, along with symbolic directions for playing the record. The contents of
this record were selected by a committee chaired by Carl Sagan.
See also
External links
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