1973-019A
The second outer planet Pioneer was Pioneer G (Pioneer 11). It was launched at 0211 on 1973 Apr 6 by Atlas Centaur. Atlas separation was at 0215, with Centaur ignition at 0216 and cutoff at 0224. The Centaur separated, and the Star 37E ignited at 0225 for 45s. It separated at 0228, and Pioneer 11 was travelling at 13.9 km/s relative to the Earth. Correction burns were made at 0550 on 1973 Apr 11, 1700 on 1974 Mar 24, and 1700 on 1974 Apr 19.
The Centaur stage entered a 513 x 102240 km x 34.42 deg orbit. This was the first flight of the SLV-3D and the Centaur D-1A, with Centaur astrionics controlling both stages.
Pioneer 11 first crossed the Jovian bow shock on 1974 Nov 27. The 42960 km closest approach was at 0522 ERT on 1974 Dec 3. The last outbound magnetosphere crossing was on Dec 8. Pioneer 11 now became Pioneer Saturn.
Pioneer Saturn made TCMs on 1975 Dec 19 and 1976 May 26 en route to the ringed planet. It passed 9.5 million km from Phoebe on 1979 Aug 27, 1 million km from Iapetus on Aug 28, and 674000 km from Hyperion on Aug 31. Inbound ring plane crossing was at 1429 on Sep 1, Dione at 291000 km at 1600, Mimas at 103000 km at 1620, closest approach to Saturn at 1630 on 1979 Sep 1 at a distance of 20900 km. Ring plane outbound was at 1824 on Sep 1; around the same time came the 332000 km and 225000 km closest approaches to Tethys and Enceladus respectively. Rhea passed by at 342000 km 6 hr after Saturn periapsis, while observations of Titan were made on Sep 2. Pioneer 11 also rediscovered satellite Janus (1979 S1) at a range of only 2500 km at 1452 on Sep 1.
By 1992 Oct 9, Pioneer 11 was 36AU from the Sun. The last communication from Pioneer 11 was received in Nov 1995, as RTG power levels fell below usable levels.
| Pioneer 11 | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1973 Apr 6 | 0211:00 | Launch by Atlas Centaur/Star 37E | |
| T+2:19 BECO | |||
| T+2:22 Booster sep | |||
| T+3:04 Jettison insulation panels | |||
| T+4:08 SECO | |||
| 0215:10 | T+4:10 Atlas sep | ||
| 0215:20 | T+4:20 Centaur MES | ||
| T+4:32 Fairing | |||
| 0222:55 | T+11:55 Centaur MECO 60W 22N? | ||
| 85s coast | |||
| T+13:05 spinup | |||
| 0224:07 | T+13:07 MECO+72s Marman clamp release, petals open | ||
| 0224:07 | MECO+72s Centaur sep | 2399.91 126 x 105836 x 34.90 | |
| 0224:20 | MECO+85s Star 37E burn, 45s | ||
| 0225:05 | Star 37E cutoff 35W 5N? 229 km | ||
| 0226:45 | T+15:45 TECO+101s Star 37E sep | ||
| 0226:47 | Star 37E yo weight release | 229 x -22043? x 34.9 | |
| 187 x -22035 x 34.81 (Horizons) | |||
| TECO+18min Pioneer despin, RTG deploy | |||
| 0329 | Pass GEO | ||
| 0634 | Pass EL1:4 | ||
| 1323 | Pass lunar orbit | ||
| 1973 Apr 7 | 0526 | Pass sphere of inf. | |
| 2214 | Pass L1 | ||
| 1973 Apr 11 | 0550 | TCM 18s 38m/s | |
| 1974 Mar 24 | 1700 | TCM | |
| 1974 Apr 19 | 1700 | TCM, retarget for S pole | |
| 1974 Oct 3 | Jupiter sphere | ||
| 1974 Nov 27 | Bow shock first crossing | ||
| 1974 Dec 3 | 0347 | Max earth-rel vel, 53.67 km/s | |
| 1974 Dec 3 | 0442 | Jupiter, 42960 km | |
| 1974 Dec 3 | 0600? | Renamed Pioneer-Saturn | |
| 1974 Dec 8 | Last outbound crossing | ||
| 1975 Jan 29 | Exit Jupiter sphere | ||
| 1975 Dec 19 | TCM | ||
| 1976 May 26 | TCM | ||
| 1979 Jun 7 | 1500 | Enter Saturn sphere | |
| 1979 Aug 27 | Phoebe, 9.5Mkm | ||
| 1979 Aug 28 | Iapetus, 1Mkm | ||
| 1979 Aug 31 | Hyperion, 674000 km | ||
| 1979 Sep 1 | 1429 | Inbound ring plane | |
| 1452 | Janus, 2500 km | ||
| 1600 | Dione, 291000 km | ||
| 1620 | Mimas, 103000 km | ||
| 1630 | Saturn, 20900 km | ||
| 1700 | Max earth-rel velocity 66.22 km/s | ||
| 1824 | Ring plane outbound | ||
| 1824 | Tethys, 332000 km | ||
| 1824 | Enceladus, 225000 km | ||
| 2230? | Rhea, 342000 km | ||
| 1979 Sep 2 | 1804 | Titan, 353948 km | |
| 1979 Nov 26 | 1800? | Leave Saturn sphere | |
| 1992 Oct 9 | 36AU from Sun | ||
| 1995 Nov | last tx | ||
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