From the National Space Science Data Center (NSSDC):
The Galileo spacecraft flew by the Earth and Moon on Dec. 8, 1990 and Dec. 7, 1992. The image at the top of the page is a false color image of the Moon created by combining 53 images taken from three different filters on Galileo during the 1992 fly-by. (Picture contact: http://NSSDC.gsfc.nasa.gov/planetary/planetary_home.html) Pink represents highlands, blue-to-orange denote volcanic flows. The primary mission of the Galileo orbiter and probe is to explore Jupiter and its satellites. (More information on the spacecraft and mission to Jupiter is given below.) Due to the great distance to Jupiter of over 600 million kilometers, and the onboard fuel limitations, a series of planetary fly-bys have taken place in order to give Galileo a gravity assist to Jupiter:
Launch 18 Oct 1989 Venus 10 Feb 1990 Earth/Moon 1 08 Dec 1990 Gaspra 29 Oct 1991 Earth/Moon 2 08 Dec 1992 Ida 28 Aug 1993 Jupiter arrival 07 Dec 1995
These fly-bys gave Galileo an opportunity to image the Moon at various wavelengths with the Solid State Imaging (SSI) camera. The camera uses a high-resolution, 800 x 800 charge-coupled device (CCD) array with a field of view of ).46 degrees. Multi-spectral coverage is provided by an eight-position filter wheel on the camera, consisting of three broad-band filters: violet (404 nm), green (559 nm) and red (671 nm); four near-infrared filters: 727nm, 756 nm, 889 nm, and 986 nm; and one clear filter 611 nm with a very broad (440 nm) passband.
This Galileo image shows the north pole of the Moon: (Again if you want the picture it is at the above http address.)
Launch Date: 12 October 1989
Launch Vehicle: Shuttle/ Inertial Upper Stage
On-orbit mass: 2380 kg
Power System: Radioisotope Thermal Generators (RTGs) of 570 W
Release Date 13 July 1995 at 05:30 UTC
Entry Date: 07 December 1995 at 22:04 UTC (d:04 p.m. EST)
Launch Vehicle: Shuttle/Inertial Upper Stage
On-orbit mass: 335 Kg
Power System: Storage batteries of 580 W
The Galileo Mission consists of two spacecrafts: an orbiter and an atmospheric probe. Launched during the STS 34 flight of the Atlantis Orbiter, the two spacecraft were kicked out of Earth orbit by an internal upper stage (IOU) rocket, sending them careening through the inner solar system. The trajectory which the spacecraft followed was called a VEEGA (Venus-Earth- Earth Gravity Assist) traveling first in toward the sun for a gravity assist from Venus before encountering the Earth two times (spaced two years apart). These encounters with Venus and Earth allowed Galileo to gain enough velocity to get it out to Jupiter.
During the fly-bys of Venus and Earth, Galileo scientists took the opportunity to study these two planets as well as the Moon, making some unprecedented observations as a result. In addition, following each Earth fly-by, Galileo made excursions as far out in the solar system as the asteroid belt, enabling scientists to make the first close-up studies of two asteroids, Gaspra and Ida. As if this were not sufficient, Galileo scientists were fortunate to be the only ones with a direct view of the Comet Shoemaker-Levy 9 fragment impacts on Jupiter. All of this was prior to the primary missions of sending an atmospheric probe into Jupiter's atmosphere and studying Jupiter, its satellites, and its magnetosphere for two years with the orbiter.
Interplanetary studies were also made sporadically by some of the other Galileo instruments, including the dust detector, magnetometer, and various plasma and particles detectors, during its six-year journey to Jupiter.
The probe was released from the orbiter 147 days prior to its entry into the Jovian atmosphere on 7 December 1995
(Galileo is now returning data on Jupiter and its Moons.)
A comprehensive list of the scientific results of Galileo would be longer than space permits. Here, then, is a short list of some important discoveries (in no particular order).
-- Marvin Ostrega