Magnetosphere of Jupiter By 1973 the magnetic moment was known within a factor of two, whereas the tilt was correctly estimated at about 10°. The modulation of Jupiter's DAM by Io (the so-called Io-DAM) was discovered in 1964, and allowed Jupiter's rotation period to be precisely determined. The definitive discovery of the Jovian magnetic field occurred in December 1973, when the Pioneer 10 spacecraft flew near the planet. As of 2009 a total of eight spacecraft have flown around Jupiter and all have contributed to the present knowledge of the Jovian magnetosphere. The first space probe to reach Jupiter was Pioneer 10 in
The Jupiter Theft into an alien contact scenario. The "intruder" is actually the silicate core of a Jovian planet, orbited by a moon and five immense alien spacecraft. The Jupiter Mission is intercepted in mid-space by aliens, dubbed Cygnans, riding on matter-annihilation powered "broomsticks". The mission is essentially destroyed, with the surviving crew taken alive as specimens for a Cygnan zoo. Now imprisoned, the Sino-American crew attempt contact with the Cygnans and seek to discover their true purpose in appearing in the Solar System. Using a Moog synthesizer and their natural gift of perfect pitch, one of the crew learns first to understand