Pioneer 7

Pioneer 7

Spacecraft· NASAcompleted

Pioneer 7 — the second solar-weather monitor, placed in a solar orbit just outside Earth's (17 August 1966). It tracked the solar wind for nearly three decades and, in March 1986, flew within 12 million km of Halley's Comet — the closest a US spacecraft came to it.

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Key facts

Distance from Sun
0.997 AU
Status
Completed
Launched
1966

Mission & specifications

Mission

Operator
NASA
Launched
August 17, 1966
Status
Completed

Trajectory

Distance from the Sun
0.997 AU
Computed from the cached position
Distance from Earth
3,128,447 km
Computed from cached positions
Distance from Venus
0.297 AU
Computed from cached positions

Mission

Pioneer 7 was the second node of the Sun-watching network, launched on 17 August 1966 into a solar orbit just outside Earth's own. From there it monitored the solar wind and interplanetary magnetic field for nearly thirty years, part of a constellation that let scientists see solar disturbances from several places at once. Its most memorable moment came almost twenty years into its mission: in March 1986, as Halley's Comet made its famous return, the still-functioning Pioneer 7 was manoeuvred to observe it and passed within about twelve million kilometres of the comet — the closest any American spacecraft came to Halley — sampling the interaction between the comet's tail and the solar wind. It kept returning data until its final contact in 1995, a testament to how much science a simple, sturdy probe could deliver over a working life measured in decades.

  1. 1966Second network nodeLaunch

    Placed in a solar orbit just outside Earth's to watch the solar wind.

  2. 1986Passes Halley's CometFlyby

    Twenty years on, it makes the closest US approach to Halley, sampling the comet–solar-wind interaction.

  3. 1995Final contactMission end

    Returns data for nearly three decades before its last contact.

Images

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Organisations