Pioneer 10

Key facts and history

NASA approved the mission in February 1969, and the spacecraft was originally designated Pioneer F before launch.^[3] The main body of Pioneer 10 measured 36 cm in depth and had a hexagonal shape with six sides each 76 cm long; this bus contained eight of the eleven scientific instruments on board.^[4] A 2.74 m parabolic dish, built from aluminum honeycomb sandwich material, served as the spacecraft's high-gain antenna.^[5] After crossing the asteroid belt without encountering any large particles, Pioneer 10 exited the belt on approximately February 15, 1973.^[6]

Pioneer 10 became the first spacecraft to execute a gravity-assist maneuver, using Jupiter's gravitational pull to propel it out of the Solar System.^[7] The formal conclusion of the Pioneer 10 mission occurred on March 31, 1997, at which point the spacecraft was located 67 AU from the Sun.^[5]

What the cited sources add

The NASA technical report "Pioneer Odyssey: Encounter with a Giant" states that Pioneer 10 provided the first close-up pictures of Jupiter and was the first man-made object to leave the solar system.^[1] The Weebau Spaceflight Encyclopedia notes that as of January 1, 1997, Pioneer 10 was at about 67 AU from the Sun near the ecliptic plane, heading outward at 2.6 AU/year.^[8] The same source records that on February 5, 2002, Pioneer 10 was 79.66 AU from the Sun and traveling at 12.24 km/sec relative to the Sun.^[8] The Weebau Spaceflight Encyclopedia also states that until Pioneer 10 reaches about 1.5 parsec from the Sun—roughly 126,000 years from now—its path will be dominated by the Sun's gravitational field.^[8]