Pioneer 4 launched into space with the same trajectory as the short-lived Pioneer 3. Pioneer 4 became the first US spacecraft to leave the Earth’s gravitational field – it came within 59,000 kilometers (37,300 miles) of the Moon’s surface. The Pioneer antenna recorded 24 hours of telemetry from three successful ten hour passes.
Pioneer 4 launched into space with the same trajectory as the short-lived Pioneer 3. Pioneer 4 became the first U.S. spacecraft to leave the Earth’s gravitational field – it came within 59,000 kilometers (37,300 miles) of the Moon’s surface. The Pioneer antenna recorded 24 hours of telemetry from three successful ten hour passes.
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