Pioneer 7
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.
Key facts
Mission & specifications
Mission
- Operator
- NASA
- Launched
- August 17, 1966
- Status
- Completed
Trajectory
- Distance from the Sun
- 1.01 AU
- Distance from Earth
- 3,083,487 km
- Distance from Venus
- 0.616 AU
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.
- 1966Second network nodeLaunch
Placed in a solar orbit just outside Earth's to watch the solar wind.
- 1986Passes Halley's CometFlyby
Twenty years on, it makes the closest US approach to Halley, sampling the comet–solar-wind interaction.
- 1995Final contactMission end
Returns data for nearly three decades before its last contact.
Images
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