List of Footnotes

1 See details on the Pioneer missions at External Link Note that Pioneer 6 remained operational for more than 35 years after launch.
2 To generate ephemerides for solar-system bodies, including many spacecraft, one can use JPL’s HORIZONS system, which is located at: External Link
3 Customarily, the direction in which the high-gain antenna points is referred to as the “fore” (also, +z) direction, whereas the direction towards the “bottom” of the spacecraft is referred to as the “aft” (also -z) direction. Note that most of the time, the spacecraft is, in fact, traveling in the aft direction, as the HGA is pointing in the general direction towards the Earth, in a direction opposite to the direction of travel (especially in deep space).
4 Transistor-Transistor-Logic, or TTL integrated circuits are standardized logic circuits built using bipolar transistors that have been in widespread use since the 1960s in the form of small-scale integration (SSI) integrated circuits containing a small number of logic gates per chip.
5 Note that the acceleration due to nongravitational forces, regardless of their external or internal origin, is dependent on the actual mass of the spacecraft.
6 Private communication in 2008 with Jim Moses, a TRW retiree.
7 A technical description, with a history and photographs, of NASA’s Deep Space Network can be found at External Link The document describing the radio science system can be found at External Link
8 The last such upgrade was conducted for the Cassini mission when the DSN capabilities were extended to cover the Ka radio frequency bandwidth. For more information on DSN methods, techniques, and present capabilities, see [38Jump To The Next Citation Point, 374Jump To The Next Citation Point].
9 The station location in Johannesburg was a compromise; Spain would have been preferred for technical reasons. As a result of historical changes in South Africa and Spain, construction of a new DSN complex near Madrid began, and eventually, the Johannesburg facility was closed. In the meantime, there was a strong rationale to construct additional antennas in Australia at a more accessible location. The Woomera complex remained operational until Pioneer 10 was well on its way towards Jupiter, but eventually, it was superseded by a new DSN complex on Australian soil, in Tidbinbilla near Canberra.
10 See External Link\_generic.html.
11 Information on the location of DSN stations that are no longer in service was provided by W.M. Folkner of JPL via private communication. Relocation date for DSS-12 is from [241Jump To The Next Citation Point].
12 The full 400-kW power of the DSN was used on March 3 – 5 2006, when the DSN attempted to contact Pioneer 10 for the last time. Unfortunately, the lack of sufficient power resources on-board the spacecraft prevented a successful two-way communication [378].
13 Ramped transmissions were also used to compensate for a partial failure of the on-board receiver of Voyager 2.
14 We thank Craig G. Markwardt for helping us to improve this section significantly.
15 After the installation of Block V receivers, there is high time resolution Doppler data available, called “open loop” data. This data is stored in files called ODRs (Original Data Records), which became available only at the very end of the Pioneer missions and were not used as a standard format for navigating these missions in deep space [150].
16 The JPL and DSN convention for Doppler frequency shift is (Δ ν)DSN = ν0 − ν, where ν is the measured frequency and ν0 is the reference frequency. It is positive for a spacecraft receding from the tracking station (red shift), and negative for a spacecraft approaching the station (blue shift), just the opposite of the usual convention, (Δ ν)usual = ν − ν0. In consequence, the velocity shift, Δv = v − v0, has the same sign as (Δ ν)DSN but the opposite sign to (Δ ν)usual. Unless otherwise stated, we use the DSN frequency shift convention in this document.
17 Normally, MDRs are seen to be of little use once the relevant information is extracted from them. Scientific measurements are extracted, packaged in the appropriate form, and sent to the corresponding experimenters for further processing and evaluation. Engineering telemetry is used by the spacecraft operations team to control and guide the spacecraft. MDRs are not necessarily considered worth preserving once the scientific data has been extracted, and the engineering telemetry is no longer needed for spacecraft operations. Indeed, the MDR retention schedule prescribed that the tapes be destroyed after 7 years. Fortunately, most of the MDRs for the Pioneer 10 and 11 projects have been preserved nevertheless (see discussion in [397Jump To The Next Citation Point]).
18 JPL’s Orbit Determination Program, ODP, uses a higher precision conversion algorithm, not the simplified formula presented here.
19 See External Link
20 The exact number of maneuvers is unknown due to incomplete records, although most maneuvers can be reconstructed from the preserved telemetry.
21 See also External Link
22 The fuel inventory quoted in [27Jump To The Next Citation Point] is 5.8 kg. This much 238Pu would produce significantly more heat at the rate of 0.57 W/g than the known thermal power of the Pioneer RTGs. Likely, 5.8 kg was the total mass of the plutonium-molybdenum cermet pucks on board, which contained approximately 4.6 kg plutonium metal.
23 C.B. Markwardt, private communication.
24 See also External Link
25 Some ranging observations were also performed for the Pioneer spacecraft, by varying the frequency of the transmitted signal and observing the corresponding changes in the signal received from the spacecraft.
26 A fore-aft difference of 1% is possible, but not supported by any available data.
27 see External Link for details.
28 See presentation by B. Christophe, “Gravity Advanced Package, a fundamental physics experiment for Jupiter Ganymede Orbiter Mission”, at the recent Gravitation and Fundamental Physics in Space, the GPhyS “Kick-Off” Colloquium, Les Houches, 20 – 22 October, 2009, at External Link
29 The National Space Science Data Center (NSSDC), see details at External Link
30 Groupe Anomalie Pioneer (GAP), a French collaboration on Pioneer Anomaly supported by The Centre National d’Etudes Spatiales (CNES), France, which includes researchers from LKB, ONERA, OCA, IOTA and SYRTE laboratories, see details at External Link
31 See definition of the jerk term at External Link
32 The Pioneer Explorer Collaboration at the International Space Science Institute (ISSI), Bern, Switzerland, see details External Link