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
Jupiter Magnetospheric Orbiter teams for 4 of the 10 Jupiter Icy Moon Explorer (JUICE) mission instruments. Jupiter Magnetospheric Orbiter The Jupiter Magnetospheric Orbiter (木星磁気圏オービター, JMO) is a cancelled space probe proposed by the Japanese Aerospace Exploration Agency (JAXA), to undertake detailed "in situ" studies of the magnetosphere of Jupiter as a template for an astrophysical magnetised disk. The JMO was originally proposed in 2006 as the Japanese contribution to the now cancelled Europa Jupiter System Mission (EJSM). Then, it was proposed to be carried to Jupiter by the Jupiter and Trojan Asteroid Explorer (Trojan Asteroid Explorer). The discussion for the international collaboration for