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Voyager Interplanetary Mission

The Voyager mission was designed to take advantage of a rare geometric arrangement of the outer planets in the late 1970s and the 1980s which allowed for a four-planet tour for a minimum of propellant and trip time. This layout of Jupiter, Saturn, Uranus and Neptune, which occurs about every 175 years, allows a spacecraft on a particular flight path to swing from one planet to the next without the need for large onboard propulsion systems. The flyby of each planet bends the spacecraft's flight path and increases its velocity enough to deliver it to the next destination. Using this "slingshot" technique, first demonstrated with NASA's Mariner 10 Venus/Mercury mission in 1973-74, the flight time to Neptune was reduced from 30 years to 12.

The Jovian Moons

[Image: ganymede.jpg]

Voyager 1 took this picture of Ganymede from a distance of 2.6 million kilometers
(1.6 million miles) on March 4, 1979. Jupiter's largest satellite has about 1.5 times
the diameter of our Moon, but being composed of a mixture of rock and ice it's only
about half our Moon's bulk density.

[Image: io_close.jpg]

Voyager 1 took this picture of Io March 5, 1979 from 377,000 kilometers (226,200 miles)
on March 5, 1979. The smallest features visible are about 10 kilometers (6 miles) across.
The reddish, white and black areas are probably volcanic deposits of salts, sulfur and sublimates.

[Image: callisto_close.jpg]

Voyager 1 took this picture approaching Callisto from 350,000 kilometers on March 6, 1979. Jupiter's outer satellite is about 7 kilometers across on the surface -- a little smaller than Ganymede and apparently composed of a mixture of ice and rock.

[Image: europa_close.jpg]

Voyager 2 took this picture of Europa on Jul 9, 1979. The size of our moon, it's
thought to have a 100 kilometers thick crust of ice overlying the silicate crust.
The complex array of streaks indicate that the crust has been fractured and filled by
materials from the interior.

The other Voyager photos, including Saturn and the outer planets: http://nssdc.gsfc.nasa.gov/photo_gallery...yager.html

Two spacecraft were used, which have since been reprogrammed to leave the solar system, north and south of the ecliptic.


See also Gene Roddenberry's "Star Trek: The Motion Picture", where
an overhauled Voyager returns from interstellar space to find it's "Creator". [Image: smile.gif]
i saw the star trek film when it was first shown Wink

i'm surprised the usa is closing down some of it's space operations.
surely we need to explore outside our solar system if we're to survive as a species.


(07-21-2010, 06:15 AM)billy Wrote: [ -> ]i saw the star trek film when it was first shown Wink

i'm surprised the usa is closing down some of it's space operations.
surely we need to explore outside our solar system if we're to survive as a species.

The Jet Propulsion Lab in Pasadena has always given us the most bang for the buck. It continues to monitor remotely-guided missions like Voyager that are decades-old. Imagine the time lags involved. http://www.jpl.nasa.gov/missions/

Quote:Engineers Diagnosing Voyager 2 Data System

On June 28, 2010, Voyager 2 completed 12,000 days of continuous operations since its launch on August 20, 1977. For nearly 33 years, the venerable spacecraft has been returning unprecedented data about the giant outer planets, the properties of the solar wind between and beyond the planets and the interaction of the solar wind with interstellar winds in the heliosheath. Having traveled more than 21 billion kilometers on its winding path through the planets toward interstellar space, the spacecraft is now nearly 14 billion kilometers from the sun. Traveling at the speed of light, a signal from the ground takes about 12.8 hours to reach the spacecraft.

Voyager 2 is now returning properly formatted data at 160 bits per second. Commands to reset the incorrect bit were uplinked on 19 May and we confirmed via downlink on 20 May that the bit change was successful and that the Checksum was now correct. On Saturday, 22 May we commanded back to the nominal cruise mode and confirmed on Sunday that we could frame-sync on the data. All experimenters report that their data looks normal except for a timing offset. The timing offset is a result of the “wait 10 msec” FDS instructions that were executed during the anomaly. Our next action is to correct the FDS timing. We have also begun to investigate a software patch to bypass the affected memory location.

Voyager 1 will reach this milestone on July 13 after having traveled more than 22 billion kilometers. Voyager 1 is currently more than 17 billion kilometers from the Sun.
i thought the nasa budget had been cut to the bone?
i remember seeing the horse head nebula when i was young and i'm still amazed
every time i see it again.