Pioneer 9
Pioneer 9 — the last successful member of the network (launched 8 November 1968), and the one placed closest to the Sun, inside Earth's orbit. It returned solar-wind and cosmic-ray data through the 1970s; its last contact was in 1983.
Key facts
Mission & specifications
Mission
- Operator
- NASA
- Launched
- November 8, 1968
- Status
- Completed
Trajectory
- Distance from the Sun
- 1.01 AU
- Distance from Earth
- 4,633,746 km
- Distance from Venus
- 0.623 AU
Mission
Pioneer 9 completed the working solar-weather network, launched on 8 November 1968 into a solar orbit inside Earth's — closer to the Sun than any of its siblings. From that vantage it returned valuable measurements of the solar wind, cosmic rays and interplanetary magnetic field through the 1970s, and it is often credited with recording the great solar storm of August 1972, one of the most powerful of the space age. Together the four Pioneers of the network gave scientists their first sustained, multi-point view of conditions between the planets. Pioneer 9 kept working until contact was lost in 1983; after repeated attempts to reacquire its signal failed, it was formally declared inactive in 1987. Like the others, it still coasts in orbit around the Sun, a silent monument to a quietly successful mission.
- 1968The network completedLaunch
The fourth monitor, placed inside Earth's orbit — closest of the set to the Sun.
- 1983Last contactMission end
Returns solar-wind data through the 1970s; contact is lost in 1983 and it is declared inactive in 1987.
Images
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