INTERPLANETARY ORBITAL ELEMENTS FOR GALILEO December 1990 Galileo was launched on October 18, 1989, on a five-year trajectory that will take it to Jupiter. On the way, Galileo's flight path takes it on a flyby of Venus, then of Earth, then by the asteroid Gaspra, followed by another Earth flyby and an encounter with the asteroid Ida. Several months before Jupiter arrival, Galileo will release a probe which will descend into the Jovian atmosphere. The main Galileo orbiter will undertake a complex orbital tour at Jupiter including flybys of all of the giant planet's major moons. The following are classic orbital elements for the Galileo spacecraft, as provided in December 1990 by the Galileo Navigational Team at the Jet Propulsion Laboratory. The coordinate system is Earth Mean Ecliptic, 1950 Equinox. Dates (in year/month/day format) and times (in 24-hour format) are both in Universal Time (UTC), also known as Greenwich Mean Time (GMT). All elements apply to the mated Galileo orbiter and probe, with the exception of the final three sets of elements which are marked as being for the probe only. The elements for the orbiter after probe separation (July 17, 1995) are not listed but will be posted when available from the Galileo Project. _____ LAUNCH Valid from 89/10/19 01:29 to 89/10/26 01:55 Epoch 89/10/19 01:29 Central body Earth Semi-major axis (km) -2.584E4 Eccentricity 1.26 Inclination (deg) 54.9 Longitude of ascending node (deg) 157.2 Argument of periapsis (deg) -1.1 Mean anomaly 36.4 EARTH-VENUS Valid from 89/10/26 01:55 to 90/02/05 15:20 Epoch 89/10/26 01:55 Central body Sun Semi-major axis (km) 1.245E8 Eccentricity 0.20 Inclination (deg) 4.3 Longitude of ascending node (deg) 24.7 Argument of periapsis (deg) -175.3 Mean anomaly -177.3 VENUS FLYBY Valid from 90/02/05 15:20 to 90/02/14 20:56 Epoch 90/02/10 05:59 Central body Venus Semi-major axis (km) -8.555E3 Eccentricity 3.59 Inclination (deg) 134.9 Longitude of ascending node (deg) -70.6 Argument of periapsis (deg) -109.1 Mean anomaly 0.0 VENUS-EARTH Valid from 90/02/14 20:56 to 90/12/05 15:47 Epoch 90/02/14 20:56 Central body Sun Semi-major axis (km) 1.479E8 Eccentricity 0.29 Inclination (deg) 3.4 Longitude of ascending node (deg) 76.0 Argument of periapsis (deg) 106.3 Mean anomaly -10.3 EARTH 1 FLYBY Valid from 90/12/05 15:47 to 90/12/12 01:24 Epoch 90/12/08 20:35 Central body Earth Semi-major axis (km) -4.977E3 Eccentricity 2.47 Inclination (deg) 142.2 Longitude of ascending node (deg) 71.8 Argument of periapsis (deg) 95.9 Mean anomaly 0.0 EARTH-GASPRA Valid from 90/12/12 01:24 to 91/10/29 22:49 Epoch 90/12/12 01:24 Central body Sun Semi-major axis (km) 2.375E8 Eccentricity 0.43 Inclination (deg) 4.5 Longitude of ascending node (deg) -104.1 Argument of periapsis (deg) -136.8 Mean anomaly -14.9 GASPRA-EARTH Valid from 91/10/29 22:49 to 92/12/05 10:09 Epoch 91/10/29 22:49 Central body Sun Semi-major axis (km) 2.376E8 Eccentricity 0.43 Inclination (deg) 4.6 Longitude of ascending node (deg) -103.9 Argument of periapsis (deg) -137.1 Mean anomaly 143.8 EARTH 2 FLYBY Valid from 92/12/05 10:09 to 92/12/11 21:03 Epoch 92/12/08 15:35 Central body Earth Semi-major axis (km) -5.059E3 Eccentricity 2.32 Inclination (deg) 161.1 Longitude of ascending node (deg) 155.9 Argument of periapsis (deg) -136.7 Mean anomaly 0.0 EARTH-IDA Valid from 92/12/11 21:03 to 93/08/28 16:35 Epoch 92/12/11 21:03 Central body Sun Semi-major axis (km) 4.683E8 Eccentricity 0.69 Inclination (deg) 1.5 Longitude of ascending node (deg) -104.1 Argument of periapsis (deg) -173.5 Mean anomaly -0.3 IDA-JUPITER (PROBE ONLY) Valid from 93/08/28 16:35 to 95/09/14 03:12 Epoch 93/08/28 16:35 Central body Sun Semi-major axis (km) 4.693E8 Eccentricity 0.69 Inclination (deg) 1.6 Longitude of ascending node (deg) -105.3 Argument of periapsis (deg) -172.5 Mean anomaly 45.7 JUPITER APPROACH (PROBE ONLY) Valid from 95/09/14 03:12 to 95/12/07 22:04 Epoch 95/09/14 03:12 Central body Jupiter Semi-major axis (km) -4.136E6 Eccentricity 1.02 Inclination (deg) 8.0 Longitude of ascending node (deg) 27.4 Argument of periapsis (deg) 132.3 Mean anomaly -561.7 PROBE ENTRY Valid from 95/12/07 22:04 to 95/12/07 22:04 Epoch 95/12/07 22:04 Central body Jupiter Semi-major axis (km) -2.274E6 Eccentricity 1.03 Inclination (deg) 8.2 Longitude of ascending node (deg) 25.5 Argument of periapsis (deg) 134.8 Mean anomaly 0.0 - end -