Ulysses (spacecraft) - Instruments

Instruments

Radio/Plasma antennas. Two beryllium-copper antennas unreeled outwards from the body, perpendicular to the RTG and spin axis. Together this dipole spanned 72 meters. A third antenna, of hollow beryllium-copper, deployed from the body, along the spin axis opposite the dish. It was a monopole antenna, 7.5 meters long. These measured radio waves generated by plasma releases, or the plasma itself as it passed over the spacecraft. This receiver ensemble was sensitive from dc to 1 MHz.

Experiment Boom. A third type of boom, shorter and much more rigid, extended from the last side of the spacecraft, opposite the RTG. This was a hollow carbon-fiber tube, of 50 mm diameter. It can be seen in the photo as the silver rod stowed alongside the body. It carried four types of instruments. A solid-state X-ray instrument, which was composed of two silicon detectors to study X-rays from solar flares and Jupiter's aurorae. The GRB experiment consisted of two CsI scintillator crystals with photomultipliers. Two different magnetometers were mounted: a vector helium magnetometer and a fluxgate magnetometer. A two axis magnetic search coil antenna measured AC magnetic fields.

Body-Mounted Instruments. Detectors for electrons, ions, neutral gas, dust, and cosmic rays were mounted on the spacecraft body around the quiet section.

SWOOPS (Solar Wind Observations Over the Poles of the Sun) measures positive ions and electrons.

Lastly, the radio communications link could be used to search for gravitational waves (through Doppler shifts) and to probe the Sun's atmosphere through occultation. No gravitational waves were detected.

Total instrument mass is 55 kg.