--------------------------------------------------------- NSSDC Master Catalog Display Spacecraft --------------------------------------------------------- Pioneer 10 NSSDC ID: 72-012A Other Name(s) * Pioneer-F * 05860 --------------------------- Launch Date/Time: 1972-03-03 at 01:49:00 UTC On-orbit dry mass: 258.00 kg Nominal Power Output: 165.00 W --------------------------- Description This mission was the first to be sent to the outer solar system and the first to investigate the planet Jupiter, after which it followed an escape trajectory from the solar system. The spacecraft achieved its closest approach to Jupiter on December 3, 1973, when it reached approximately 2.8 Jovian radii (about 200,000 km). As of Jan. 1, 1997 Pioneer 10 was at about 67 AU from the Sun near the ecliptic plane and heading outward from the Sun at 2.6 AU/year and downstream through the heliomagnetosphere towards the tail region and interstellar space. This solar system escape direction is unique because the Voyager 1 and 2 spacecraft (and the now terminated Pioneer 11 spacecraft mission) are heading in the opposite direction towards the nose of the heliosphere in the upstream direction relative to the inflowing interstellar gas. The spacecraft is heading generally towards the red star Aldebaran, which forms the eye of Taurus (The Bull). The journey over a distance of 68 light years to Aldebaran will require about two millions years to complete. Routine tracking and project data processing operations were terminated on March 31, 1997 for budget reasons. Occasional tracking continues under support of the Lunar Prospector project at NASA Ames Research Center with retrieval of energetic particle and radio science data; this is expected to continue at least through mid-1998. Fifteen experiments were carried to study the interplanetary and planetary magnetic fields; solar wind parameters; cosmic rays; transition region of the heliosphere; neutral hydrogen abundance; distribution, size, mass, flux, and velocity of dust particles; Jovian aurorae; Jovian radio waves; atmosphere of Jupiter and some of its satellites, particularly Io; and to photograph Jupiter and its satellites. Instruments carried for these experiments were magnetometer, plasma analyzer, charged particle detector, ionizing detector, non-imaging telescopes with overlapping fields of view to detect sunlight reflected from passing meteoroids, sealed pressurized cells of argon and nitrogen gas for measuring the penetration of meteoroids, UV photometer, IR radiometer, and an imaging photopolarimeter, which produced photographs and measured polarization. Further scientific information was obtained from the tracking and occultation data. The spacecraft body was mounted behind a 2.74-m-diameter parabolic dish antenna that was 46 cm deep. The spacecraft structure was a 36-cm-deep flat equipment compartment, the top and bottom being regular hexagons. Its sides were 71 cm long. One side joined a smaller compartment that carried the scientific experiments. The high-gain antenna feed was situated on three struts, which projected forward about 1.2 m. This feed was topped with a medium-gain antenna. A low-gain omnidirectional antenna extended about 0.76 m behind the equipment compartment and was mounted below the high-gain antenna. Power for the spacecraft was obtained by four SNAP-19 radioisotope thermonuclear generators (RTG), which were held about 3 m from the center of the spacecraft by two three-rod trusses 120 deg apart. A third boom extended 6.6 m from the experiment compartment to hold the magnetometer away from the spacecraft. The four RTG's generated about 155 W at launch and decayed to approximately 140 W by the time the spacecraft reached Jupiter, 21 months after launch. There were three reference sensors: a star sensor for Canopus which failed shortly after Jupiter encounter and two sun sensors. Attitude position could be calculated from the reference directions to the earth and the sun, with the known direction to Canopus as a backup. Three pairs of rocket thrusters provided spin-rate control and changed the velocity of the spacecraft, the spin period near the end of the mission being 14.1 seconds. These thrusters could be pulsed or fired steadily by command. The spacecraft was temperature-controlled between minus 23 deg C and plus 38 deg C. A plaque was mounted on the spacecraft body with drawings depicting a man, a woman, and the location of the sun and the earth in our galaxy. Communications were maintained via (1) the omnidirectional and medium-gain antennas which operated together while connected to one receiver and (2) the high-gain antenna which was connected to another receiver. These receivers could be interchanged by command to provide some redundancy. Two radio transmitters, coupled to two traveling-wave tube amplifiers, produced 8 W at 2292 MHz each. Uplink was accomplished at 2110 MHz, while data transmission downlink was at 2292 MHz. The data were received by NASA's Deep Space Network (DSN) at bit rates up to 2048 bps enroute to Jupiter and at 16 bps near end of the mission. Space experiments mostly continued to operate for planetary or interplanetary measurements until failure or until insufficient spacecraft power from the RTG's was available for operation of all instruments, such that some were turned off permanently and others were cycled on and off in accordance with a power sharing plan implemented in September 1989. The Asteroid/Meteroid Detector failed in December 1973, followed by the Helium Vector Magnetometer (HVM) in November 1975 and the Infrared Radiometer in January 1974. The Meteroid Detector was turned off in October 1980 due to inactive sensors at low temperatures. The spacecraft sun sensors became inoperative in May 1986, and the Imaging Photopolarimeter (IPP) instrument was used to obtain roll phase and spin period information until being turned off in October 1993 to conserve power. The Trapped Radiation Detector (TRD) and Plasma Analyzer (PA) were respectively turned off in November 1993 and September 1995 for the same reason. As of January 1996 the final power cycling plan included part-time operations of the Charged Particle Instrument (CPI), the Cosmic Ray Telescope (CRT), the Geiger Tube Telescope (GTT), and the Ultraviolet Photometer (UV). Power availability for operation of one or more instruments was expected to continue at least through 1998. Currently, the GTT and CPI instruments are still returning data during occasional tracking intervals; GTT operates nominally, returning data whenever tracking takes place (there is no onboard tape recorder), while CPI is cycled on for about four hours every two weeks. Three-way doppler data for radio science are also obtained during some tracking intervals. Various other spacecraft subsystems also either failed or were turned off for power or other reasons, and an account of these may be of interest for engineering design of long duration deep space missions. The primary antenna feed offset bellows failed sometime in 1976 but a redundant unit was available for use thereafter. The Program Storage and Execution (PSE) subsystem was turned off in September 1989 for power conservation, after which spacecraft maneuvers were performed by ground command sequences. A receiver problem in mid-1992 prevented uplink to the high gain antenna, after which uplink commands could only be sent with 70-meter DSN antennas which also supported the 16 bps downlink. The Backup Line Heater experienced a sticking thermostat operation in March 1993 for 30 days but the problem did not reoccur. Undervoltage Protection Logic was turned off in December 1993 to prevent loss of critical spacecraft systems in the event of a transient undervoltage condition. Duration and Steering Logic (DSL) was turned off in February 1995 to conserve power, after which it was turned on again only for spacecraft maneuvers. As of March 2, 1998 two experiments (GTT, CPI) were still active. RTG power levels are low enough that the spacecraft occasionally relies in part on battery power (accumulated during inactive periods) to run the experiments and other systems. ------------------- Discipline(s) Astronomy Planetary Science Space Physics Sponsoring Agencies/Countries NASA-Office of Space Science Applications/United States --------------------------------------------------------- NSSDC Master Catalog Display Spacecraft Launch/Orbital Information --------------------------------------------------------- Pioneer 10 NSSDC ID: 72-012A Launch Information Launch Date/Time: 1972-03-03 at 01:49:00 UTC Launch Site/Country: Cape Canaveral, United States Launch Vehicle: Atlas-Centaur Orbital Information Orbit: Interplanetary cruise Central Body: Sun Epoch start date/time: 1972.063:01:49:00 (03 Mar.) Epoch end date/time: 1973.338:02:25:00 (04 Dec.) Orbital Period: 2368.33 d Inclination: 1.92 degrees Eccentricity: 0.71514 Periapsis: 0.99 AU Apoapsis: 5.97 AU ------------------- Orbit: Flyby Central Body: Jupiter Closest approach date/time: 1973.338:02:25:00 (04 Dec.) Inclination: 13.80 degrees Periapsis: 2.85 AU Apoapsis: 13.80 AU ------------------- Orbit: Solar system escape Central Body: Sun Epoch start date/time: 1973.338:02:25:01 (04 Dec.) Inclination: 3.14 degrees Eccentricity: 1.74 Periapsis: 5.10 AU ------------------- --------------------------------------------------------- NSSDC Master Catalog Display Spacecraft Telecommunications Information --------------------------------------------------------- Pioneer 10 NSSDC ID: 72-012A Telemetry rates: 0.016 - 2.048 kbps Effective Telemetry Rate: 0.450 kbps Telemetry support via Deep Space Network (DSN) Description The DSN supported the Pioneer spacecraft deep space tracking, uplink commands, and downlink data acquisition during the mission with 26-m, 34-m, 64-m, and 70-m antennas at Goldstone, Madrid, and Canberra. Overlapping coverage by two stations was used to prevent loss of data. The spacecraft carried three antennas for reception and transmission - low gain (omnidirectional), medium gain, and high gain (beamed) - with pairs of redundant transmitters and receivers, so the ground uplink and downlink DSN antennas could be switched between the different antenna sizes to accommodate telemetry demands from other missions. Downlink telemetry bit rates were at a maximum of 2048 bps enroute to Jupiter and 1024 bps at Jupiter but were maintained at 1024 bps out to Saturn's orbit due to increases in DSN antenna sensitivity. Reduced bit rates were required during superior conjunctions with the Sun. Pioneer 10 could receive uplink commands only (due to a receiver problem preventing use of the high gain antenna) from the 70-m antennas at 55 AU from the Sun in mid-1992, and the 70-mt antennas were needed to maintain the downlink bit rate at 16 bps. Routine tracking ceased on March 31, 1997, although the still operable spacecraft continued to be tracked occasionally through 1998 as part of training exercises for operators of the Lunar Prospector spacecraft. Limited 70 meter DSN coverage was expected to be available at least through June of 1998. --------------------------------------------------------- NSSDC Master Catalog Display Spacecraft Personnel --------------------------------------------------------- Pioneer 10 NSSDC ID: 72-012A Program Manager Dr. James B. Willett Code SS NASA Headquarters Washington, DC 20546 Electronic Mail WILLETT@USRA.EDU (INTERNET) NHQVAX::JWILLETT (NSI/DECNET) ----- Program Scientist Dr. W. Vernon Jones Code SR NASA Headquarters Washington, DC 20546 Electronic Mail WVJONES@NHQVAX.DNET.NASA.GOV (INTERNET) NHQVAX::WVJONES (NSI/DECNET) ----- Project Manager Mr. Richard O. Fimmel Mail Stop 244-8 NASA Ames Research Center Moffett Field, CA 94035 ----- Project Scientist Dr. Palmer Dyal Mail Stop 200-7 Astrophysics Branch NASA Ames Research Center Moffett Field, CA 94035 ----- NSSDC Contact Dr. John F. Cooper GSFC-Code 632 Electronic Mail JCOOPER@NSSDCA.GSFC.NASA.GOV (INTERNET) NCF::JCOOPER (NSI/DECNET) ----- --------------------------------------------------------- NSSDC Master Catalog Display Spacecraft Selected References --------------------------------------------------------- Pioneer 10 NSSDC ID: 72-012A 1. Fimmel, R. O., Swindell, W., and Burgess, E., Pioneer odyssey encounter with a giant, NASA, SP-349, Washington, D.C., 1974. 2. Fimmel, R. O., Van Allen, J. A., and Burgess, E., Pioneer first to Jupiter, Saturn and beyond, NASA, SP-466, Washington, D.C., 1980. 3. Hall, C. F., Pioneer 10, Science, 183, No. 4122, 301-302, Jan. 1974. --------------------------------------------------------------------------- For questions about this mission, please contact: Dr. John F. Cooper, jcooper@nssdca.gsfc.nasa.gov, (301)286-1193 GSFC-Code 632 [Logo] For questions about the NSSDC's information systems, please contact: Dr. James Thieman, thieman@nssdca.gsfc.nasa.gov, (301)286-9790 National Space Science Data Center, Code 633.2 NASA/Goddard Space Flight Center, Greenbelt, MD 20771 --------------------------------------------------------------------------- NASA Official: J. H. King, king@nssdca.gsfc.nasa.gov Last Updated: 1996-08-29 Output Generated: 1996-09-16 Programming by: E. V. Bell, II