The first mission to study the sun from its north and south poles launched 26 years ago yesterday: the Ulysses mission.
Ulysses. Image Credit: NASA/JPL
Ulysses was a joint mission between NASA and the European Space Agency (ESA). It launched from Cape Canaveral on October 6, 1990 aboard NASA’s Space Shuttle Discovery.
The mission’s primary purpose was to characterize the heliosphere. What’s the heliosphere? It’s the magnetic bubble that contains our solar system. The heliosphere includes the solar wind and solar magnetic field.
Ulysses investigated the heliosphere from high latitudes, 70 degrees or higher at both poles. Before this mission, previous spacecraft had only been able to reach a latitude of 32 degrees.
The mission studied the magnetic forces of the sun’s upper atmosphere. It investigated the very structure of the sun and solar wind interference. Ulysses also examined solar radio bursts and plasma waves as well as solar X-rays. It taught us about energetic particles that came from solar storms and galactic cosmic radiation.
Not limited to only studying the sun, Ulysses also studied Jupiter’s magnetosphere when it did a flyby of the planet. This was to position the spacecraft in an orbit that was outside of the ecliptic plane as it headed back toward the sun. The ecliptic plane is the plane in which most planets and satellites orbit the sun. Ulysses also investigated comets.
Artist’s concept of Ulysses at Jupiter. Image Credit: NASA/European Space Agency
Ulysses lasted much longer than its expected lifetime of 5 years – it was operating for almost 20 years! This was especially useful as activity of the sun varies on a cycle that lasts 11 years, and Ulysses studied the sun for almost two cycles.
More than a thousand scientific articles have come from the Ulysses mission.
Learn more about this historic mission at NASA.gov.