1977-076A
Voyager SC3 (Voyager 2, VGR-2) was launched at 1429:44 on 1977 Aug 20 by Titan IIIE Centaur from LC41 at Cape Canaveral. Although it immediately encountered problems with its science boom and other systems, these were soon resolved and it would become probably the most successful probe ever, visiting four planets and revolutionizing our knowledge of the outer solar system.
The Centaur stage cutoff into an orbit with an aphelion of around 2.8AU. The VGR propulsion module - a Star 37 motor - fired to increase aphelion to 6.3AU.
The scan platform stuck during deployment; an attempt to shake it by jettisoning a dust cover failed when the command sent VGR-2 into safemode.
VGR-2 settled into Cruise mode on Sep 2, and made a TCM on Oct 11. However, the success of launch led to complacency and the Voyager program ran into management problems at this time, with operations errors nearly losing the vehicle. Many Voyager team members moved on to work on the future Galileo project, with Voyager project manager John Casani's attention had been split between Voyager and Galileo Bob Parks was brought in to take over Voyager full-time in April 1978, soon after a crisis in which the main radio receiver switched to the backup when no message was sent to the spacecraft for over a week. A capacitor in the backup shorted, but when controllers ordered a switch back to the main reciever it failed permanently, and a week later the backup cut back in, to be used thereafter.
The first Jupiter imaging was done on 1979 Apr 24, with Jupiter Observatory Phase starting in May 1979. TCMs on May 26 and Jun 27 were made before encounter on Jul 9. TCM5, 6 and 7 were made on Jul 9, Jul 23 and 1981 Feb 26.
The Saturn Observatory Phase began on 1981 Jun 5. TCM-8 on Jul 19 and TCM-9 on Aug 18 set up the final encounter geometry. Far Encounter phases 1 and 2 began on Jul 31 and Aug 11 respectively, with Near Encounter on Aug 25. Periapsis was at 0324 on Aug 26. Voyager 2 crossed the ring plane at the G ring at 0415. The scan platform failed at 0514 on Aug 26, but most of the imaging had been taken. A Saturn Post Encounter phase lasted from Aug 27 to Sep 28.
Voyager 2 was now on course for Uranus. TCM-10 (1981 Sep 29), TCM-11 (1984 Nov 13), and another TCM on 1985 Dec 24 set up the encounter, which happened on 1986 Jan 26. The results were eclipsed by the loss of the Space Shuttle Challenger two days later.
During the Neptune cruise phase, TCM B15 (1987 Mar 13), TCM B16 (late 1988), TCMB17C (1989 Apr 20), TCM B18 (about 1989 Aug 1) and TCM B20 (1989 Aug 21) set up the accurate flyby. The Neptune Observatory Phase began on Jun 5, and transitioned to Far Encounter on Aug 6 and Near Encounter on Aug 24. Voyager 2 encountered Neptune at a distance of 4h 6min from Earth. At 2356 on Aug 24, it passed 4.6 million km from Nereid; at 0253 on Aug 25 it crossed the Neptune ring plane inbound. Closest approach to Neptune was 4905 km at 0355. The ring plane was traversed outbound at 0514, and Voyager 2 made its final flyby, of Triton, at a distance of 38360 km on 1989 Aug 25 at 0919. A Neptune Post Encounter phase from Aug 20 to Oct 2 marked the end of the Voyager outer planets exploratory mission. Voyager now began the search for the heliopause - the boundary between the solar system and interstellar space. Beginning of the Voyager Interstellar Mission was declared on 1990 Jan 1. By 1992 Oct 9, Voyager 2 was 38 AU from the Sun.
In 1999, five experiments were still operating: the CR, LEPI, PSI, PWI, and MAG.
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| Voyager 2 |
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| Date | Time | Event | Orbit |
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| 1977 Aug 20 | 1429:44 | Launch by TC | CC LC41 |
| | | T+1:50 SRM cutoff |
| | | T+1:51 St 1 burn |
| | | T+2:02 SRM sep |
| | | T+4:15 St 1 MECO |
| | | T+4:15 St 1 sep, St 2 MES |
| | | T+4:26 CSS jettison |
| | | T+7:44 St 2 MECO |
| | | T+7:50 St 2 sep |
| | | T+8:01 TC MES-1 |
| | 1439:25 | T+9:48 TC MECO-1 | 167 x 167 x 37.6 |
| | | T+53:00? Science boom deploy failed |
| | 1523:20 | T+53:36 TC MES-2 |
| | 1527:52 | T+59:16 TC MECO-2 | 195 x -29536 x 41.87 |
| | 1530:42 | T+1:02:06 TC sep |
| | | T+1:02:08 TC avoidance |
| | 1530:58 | T+1:02:21s PMI burn |
| | 1531:40 | T+1:03:06 PM burnout | 326 x -20835 x 41.86 |
| | 1543:01 | T+1:12:33 PM sep |
| | 1937 | VGR pass EL1:4 |
| | 2050 | Centaur pass EL1:4 |
| 1977 Aug 21 | 0200 | VGR pass lunar orbit |
| 1977 Aug 21 | 1600? | VGR exit SOI/929 at Vinf=10.14 km/s |
| 1977 Aug 22 | 0824 | VGR exit SOI/L1 |
| 1977 Aug 22 | 0300? | Centaur exit Earth SOI (929k) at Vinf = 6.93 km/s | 1.02 x 3.02 AU x 3.7 deg? |
| 1977 Aug 23 | 0215? | Centaur exit Earth Hill sphere per orbit soln |
| 1977 Aug 26 | | Attempt to jettison IRIS cover aborted |
| 1977 Aug 29 | | IRIS cover jettisoed |
| 1977 Sep 2 | | Begin cruise |
| 1977 Oct 11 | | TCM B-1 |
| 1978 Apr | | Main radio receiver fail |
| 1978 May 3 | | TCM B-2 |
| 1979 Apr 24 | | First Jupiter image |
| 1979 Apr 30 | 1830? | Enter Jupiter sphere |
| 1979 May 1 | | 48M km from Jupiter |
| 1979 May | | Jupiter Observatory Phase |
| 1979 May 26 | | TCM B-3 |
| 1979 Jun 27 | | TCM B-4 |
| 1979 Jul 8 | | Jupiter Near Encounter |
| 1979 Jul 8 | 1313 | Callisto, 214930 km C/A |
| 1979 Jul 9 | 0806 | Ganymede, 62130 km C/A |
| | 0850 | Max earth-rel velocity 55.91 km/s |
| | 1843 | Europa, 205720 km C/A |
| | 2030? | Amalthea 558370 km C/A |
| | 2229:00 | Jupiter, 650178 km (721670 km C/A) |
| 1979 Jul 9 | | TCM B-5 peri+2hr, 76min |
| 1979 Jul 23 | | TCM B-6 |
| 1979 Aug 5 | | Cruise phase |
| 1979 Sep 18 | 0240? | Exit Jupiter sphere |
| 1979 Sep 23 | | 48Mkm from Jupiter |
| 1981 Feb 26 | | TCM B-7 |
| 1981 Jun 5 | | Saturn Observatory Phase, 77 Mkm |
| 1981 Jun 18 | 2000? | Enter Saturn sphere 64.5M |
| 1981 Jun 22 | | 55 Mkm from Saturn |
| 1981 Jul 19 | | TCM B-8 |
| 1981 Jul 31 | | Saturn Far Encounter 1 |
| 1981 Aug 11 | | Saturn Far Encounter 2 |
| 1981 Aug 18 | | TCM B-9 |
| 1981 Aug 25 | | Saturn Near Encounter |
| 1981 Aug 23 | 0127 | Iapetus, 908680 km C/A |
| 1981 Aug 25 | 0125 | Hyperion 471370 km C/A |
| 1981 Aug 25 | 0937 | Titan 666190 km C/A |
| | 2258 | Helene, 270000 km C/A |
| 1981 Aug 26 | 0105 | Dione, 502310 km C/A |
| | 0222 | Calypso, 200000? km C/A |
| | 0234 | Mimas, 309930 km C/A |
| | 0308 | Atlas, 287000 km C/A |
| | 0319 | Pandora, 107000 km C/A |
| 1981 Aug 26 | 0324 | Saturn, 100800 km |
| | 0333 | Prometheus, 247000 km C/A |
| | 0345 | Enceladus, 87010 km C/A |
| | 0350 | Janus, 223000 km C/A |
| | 0406 | Epimetheus, 147000 km C/A |
| | 0415 | Ring plane crossing, in G ring |
| | 0440 | Max earth-rel velocity, 61.7 km/s |
| | 0514 | Scan platform fail |
| | 0603 | Telesto, 300000 km? |
| | 0612 | Tethys, 93010 km C/A |
| | 0629 | Rhea, 645260 km C/A |
| 1981 Aug 27 | | Saturn Post Encounter |
| 1981 Sep 4 | 0130? | Phoebe, 2075640 km C/A |
| 1981 Sep 28 | | Cruise Phase |
| 1981 Sep 29 | | TCM-10 |
| 1981 Nov 2 | 1030? | 64.5M exit Saturn SOI |
| 1981 Nov 10 | | 55Mkm exit Saturn SOI |
| 1984 Nov 13 | | TCM-11 |
| 1985 Nov 4 | | Uranus Observatory Phase 103 Mkm |
| 1985 Dec 1 | 0430? | 69.6M enter U SOI |
| 1985 Dec 24 | | TCM-12? |
| 1985 Dec 31 | | Uranus SOI |
| 1986 Jan 24 | | Uranus near encounter |
| | 1530? | Titania, 365200 km C/A |
| | 1600? | Oberon, 470600 km C/A |
| | 1700? | Ariel, 127000 km C/A |
| 1986 Jan 24 | 1730? | Miranda, 28260 km C/A |
| 1986 Jan 24 | 1759 | Uranus 81541 km (71000 km old) (107100 km C/A) |
| | 1800? | Umbriel, 325000 km C/A |
| 1986 Feb 25 | | Cruise phase |
| 1986 Mar 20 | 0630? | Leave Uranus Sphere 69.6M |
| 1987 Mar 13 | | TCM B15 |
| 1988 late | | TCM B16 |
| 1988 Nov 11 | | TCM B17B 0.45 km/s |
| 1989 Apr 20 | | TCM B17C 0.3 km/s |
| 1989 Jun 5 | | Neptune Observatory Phase |
| 1989 Jun 6 | 1200 | N Sphere 115.2M |
| 1989 Jun 30 | | Neptune SOI 87Mkm |
| 1989 Aug 1 | | TCM B18 0.92 km/s |
| 1989 Aug 6 | | Neptune Far Encounter |
| 1989 Aug 21 | | TCM B20 0.47 km/s |
| 1989 Aug 24 | | Neptune Near Encounter |
| | 2356 | Nereid, 4.6Mkm |
| 1989 Aug 25 | 0253 | Ring plane inbound |
| 1989 Aug 25 | 0356 | Neptune, 4476 (old 4905 km) (29242+-2 km C/A) |
| | 0514 | Ring plane outbound |
| | 0910 | Triton, 38360 km (39780+-20 km C/A) |
| 1989 Aug 26 | | Post Encounter |
| 1989 Oct 2 | | Cruise |
| 1989 Oct 25 | | Leave Neptune SOI |
| 1989 Nov 12 | 2000? | Leave Neptune sphere 115.2M |
| 1990 Jan 1 | | Voyager Interstellar Mission |
| 1998 Nov 12 | | Comms lost |
| 1998 Nov 14 | | Comms restored |
| 1998 Nov | | Scan platform turned off |
| 1999 Feb 1 | | OWLT 16 hr |
| 2007 Aug 30 | | First helioshock pass at 84AU |
Payload:
- MHW RTG
- Imaging TV cameras (2), 1500mm f/8.5 narrow angle, 200mm f/3 wide angle
- UVS Ultraviolet spectrometer 534-1701A Plasma spectrometers
- IRIS IR spectrometer/radiometer
- LEPI Low energy charged particle analyser/telescope
- Multifilter photometer 2200-7300A, 8-in, F/1.1 scope
- Triaxial fluxgate magnetometers
