Pioneer 5
Pioneer 5 — the first spacecraft to return data from deep interplanetary space (launched 11 March 1960). From a solar orbit between Earth and Venus it made the first map of the interplanetary magnetic field, staying in contact to a record 36 million km. It still circles the Sun, silent since June 1960.
Key facts
Mission & specifications
Mission
- Operator
- NASA
- Launched
- March 11, 1960
- Status
- Completed
Trajectory
- Distance from the Sun
- 1.01 AU
- Distance from Earth
- 1,531,390 km
- Distance from Venus
- 0.609 AU
Mission
Pioneer 5 opened the true interplanetary age. Where the earlier Pioneers had reached for the Moon, this small sphere with four solar paddles was sent, on 11 March 1960, into the empty space between the orbits of Earth and Venus to find out what was actually there. It became the first spacecraft to return data from deep interplanetary space, and over three and a half months it made the first map of the interplanetary magnetic field — confirming that the Sun's influence reaches far out as a real, measurable field threading the void. It carried a pioneering digital telemetry system and stayed in contact to a record thirty-six million kilometres, until its signal grew too faint to hear in late June 1960. Silent ever since, Pioneer 5 still circles the Sun, a derelict that proved interplanetary space could be explored.
- 1960Into interplanetary spaceLaunch
Launched into solar orbit between Earth and Venus to sound the space between the planets.
- 1960Mapping the magnetic fieldMilestone
Returns the first measurements of the interplanetary magnetic field from deep space.
- 1960Last contact at 36 million kmMission end
Its signal, tracked to a record 36 million km, finally fades; it remains a derelict circling the Sun.
Images
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