Ulysses Credit - NASA

Ulysses was a joint NASA / ESA mission designed to study the polar regions of the Sun. The spacecraft was placed by a Titan 3E booster on a trajectory that intercepted Jupiter and used the giant planet's gravity to torque the orbit into one far beyond the solar system's ecliptic plane. Ulysses' first pass above the Sun's southern pole was completed in November 1994, and its first pass above the northern pole was completed in October 1995, ending the primary mission. The mission was subsequently extended to permit further observations.

Originally named the International Solar Polar Mission, Ulysses' primary scientific objectives were to investigate, as a function of solar latitude, the properties of the solar corona, the solar wind, the structure of the Sun-wind interaction, the heliospheric magnetic field, solar and non-solar cosmic rays, solar radio bursts and plasma waves, solar x-rays, and interstellar / interplanetary neutral gas and dust.

The spacecraft was spin stabilized at 5 rpm (Earth pointing). X-, and S- band communications used a 1.65 m high gain antenna. Radioisotope thermal generators were used for power generation, and provided 285 W (BOL). A hydrazine propulsion provided for trajectory correction maneuvers. Redundant tape recorders stored 46 Mb each. Three deployable booms were used for science instruments.

Ulysses carried 9 instruments in addition to using the radio system for scientific investigations. Total payload mass was 55 kg. The experiments included:

• Magnetometer (VHM/FGM) - designed to measure changes in the interplanetary magnetic field at different heliographic latitudes
• Solar Wind Plasma Experiment (SWOOPS) - studied protons, electrons and heavy ions in the solar wind and their dependence on distance from the Sun and heliospheric latitude
• Solar Wind Ion Composition Instrument (SWICS) - studied the elemental and ionic-charge composition, and the mean temperatures and mean speeds of all solar-wind ions from hydrogen to iron
• Unified Radio and Plasma Wave Instrument (URAP) - designed to determine the direction and polarization of distant radio sources, as well as radio bursts from charged particles in the solar wind
• Energetic Particle Instrument (EPAC) - measured intensities and energies of interplanetary ions to resolve their masses and to observe helium penetrating the heliosphere from interstellar space
• Heliosphere Instrument for Spectral, Composition and Anisotropy at Low Energies (HISCALE) - designed to measure elemental abundances of interplanetary ions and electrons
• Cosmic Ray and Solar Particle Instrument (COSPIN) - resolved outstanding problems in solar, interplanetary and cosmic-ray physics for which observations far out of the ecliptic plane were required
• Solar X-Ray and Cosmic Gamma-Ray Burst Instrument (GRB) - measured electrons in solar flares and determined the direction of gamma-ray bursts from distant galaxies
• Cosmic Dust Experiment (CDE) - provided direct observations of particulate matter and its interaction with solar radiation as a function of ecliptic latitude.

Design Life: 5 years. Typical orbit: Solar polar using Jupiter gravity for plane change. Length: 3.00 m (9.80 ft). Maximum Diameter: 2.00 m (6.50 ft). Mass: 367 kg (809 lb).

• 1990 October 6 - Ulysses - Launch Site: Cape Canaveral. Launch Complex: LC39B. Launch Vehicle: Shuttle. Mass: 367 kg (809 lb). Perigee: 285 km (177 mi). Apogee: 300 km (180 mi). Inclination: 28.40 deg. Period: 90.10 min.
  Deployed from STS 41 10/6/90; solar research. Ulysses is a scientific spacecraft, within the framework of the international solar/polar mission. It will be the first spacecraft to fly over the poles of the sun. Frequency 2111.6073/2293.1481 MHz, 8408.2099 MHz., interplanetary trajectory i nto a polar flyby over the sun. Designator ESA/90/01. Also registered by the United States in ST/SG/SER.E/250, orbital data are taken from that document.

• 1992 February 8 - Ulysses Flyby of Jupiter -
  

• 1994 November 1 - Ulysses' first pass above the Sun's southern pole completed -
  

• 1995 October 1 - Ulysses' first pass above the Sun's north pole completed -
  This ended the primary mission. The mission was subsequently extended to permit further observations.

• 2004 February 4 - Ulysses Closest Approach To Jupiter (0.8 AU) -