The main energy for the drive receives Ulysses from a plutonium reactor, whose natural lifetime is limited by the progressive decay of the radioactive substance, however. During the past few years, the amount of energy has been steadily decreasing, which is why some of the leaders of the mission decided not to switch off permanently needed systems like the transmitter. The sixty watts obtained in this way should also be used for the operation of the scientific measuring instruments and the heating system.
In a test run in January, the staff of the space authorities were not able to put the transmitter back on. After many failed attempts, the Ulysses team now believes that the transmitter is lost and the extra energy has never reached the other systems. "We expect some parts of the probe to reach two degrees soon, " says Richard Marsden, ESA's Ulysses Head of Mission. "However, we will squeeze the last drop of science out of the mission by then." Despite the approaching end, the helper's supervisors can still be satisfied: Ulysses is already flying four times longer than expected.Communication from the ESA ddp / science.de? Livia Rasche advertisement