The Ulysses Mission
Publication date: 01 January 1998
Authors: Smith, E.J., Marsden, R.G.
Journal: Scientific American
Page: pp. 52-57
For much of the past four decades, the scientific probes sent into space stayed relatively close to the equatorial plane of the Sun, which contains the orbits of Earth and other planets. But a few years ago a single craft, Ulysses, ventured out of that thin zone and into the 'polar regions' of interplanetary space.