THE original Ulysses took ten years to return home from Troy. On the way he encountered all sorts of monsters, lovers and other hazards. A latter-day Ulysses is taking just five and a half years to get back to where it started-and the only dangers it faces are charged particles, stray extraterrestrials and cosmic rays. For this Ulysses is a spacecraft, and in a few months' time it will have completed its first full orbit of the sun. Unlike most of the familiar things that orbit the sun-planets, asteroids and even other spacecraft-Ulysses does not circulate in the plane of the ecliptic (the region of the solar system that is analogous to the earth's equator). Instead, its orbit is almost perpendicular to that plane.
Ulysses was launched in 1990 on a five-year mission to study the sun. The craft gathered new data about the speed and direction of the solar wind. It discovered the 3D shape of the sun's magnetic field. It recorded solar flares on the sun, and super-solar flares from distant neutron stars. Ulysses even flew through the tail of comet Hyakutake, an unexpected encounter that delighted astronomers. The mission was supposed to end in 1995, but Ulysses was too successful to quit. NASA and the ESA have granted extensions after extensions. A milestone was reached on June 10th 2011 when Ulysses became the longest-running ESA-operated spacecraft, overtaking the International Ultraviolet Explorer which logged 18 years and 246 days of operations. At present The Ulysses orbital path is carrying the spacecraft away from Earth. The ever-widening gap has progressively limited the amount of data transmitted. Ulysses project managers, with the concurrence of ESA and NASA, decided it was an appropriate time now to end this epic scientific adventure.
The 7c Europa stamp issued by Cyprus depicts the European spaceship "Ulysses" launched in October 1990 from the shuttle "Atlantis". Its objective was to study some parts of the Sun, the solar wind, the cosmic rays, and to trace gravity waves. This nice maxicard was given to me by Merja.
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