Galileo trajectory design

The Galileo spacecraft was launched by the Space Shuttle Atlantis on October 18, 1989. A two-stage Inertial Upper Stage propelled Galileo out of Earth parking orbit to begin its 6-year interplanetary transfer to Jupiter. Galileo has already received two gravity assists: from Venus on February 10, 1990 and from Earth on December 8, 1990. After a second gravity-assist flyby of Earth on December 8, 1992, Galileo will have achieved the energy necessary to reach Jupiter. Galileo's interplanetary trajectory includes a close flyby of asteroid 951-Gaspra on October 29, 1991, and, depending on propellant availability and other factors, there may be a second asteroid flyby of 243-Ida on August 28, 1993. Upon arrival at Jupiter on December 7, 1995, the Galileo Orbiter will relay data back to Earth from an atmospheric Probe which is released five months earlier. For about 75 min, data is transmitted to the Orbiter from the Probe as it descends on a parachute to a pressure depth of 20–30 bars in the Jovian atmosphere. Shortly after the end of Probe relay, the Orbiter ignites its rocket motor to insert into orbit about Jupiter. The orbital phase of the mission, referred to as the satellite tour, lasts nearly two years, during which time Galileo will complete 10 orbits about Jupiter. On each of these orbits, there will be a close encounter with one of the three outermost Galilean satellites (Europa, Ganymede, and Callisto). The gravity assist from each satellite is designed to target the spacecraft to the next encounter with minimal expenditure of propellant. The nominal mission is scheduled to end in October 1997 when the Orbiter enters Jupiter's magnetotail.

ASI:

Atmospheric Structure Instrument

EPI:

Energetic Particles Instrument

HGA:

High Gain Antenna

IUS:

Inertial Upper Stage

JOI:

Jupiter Orbit Insertion

JPL:

Jet Propulsion Laboratory

LRD:

Lightning and Radio Emissions Detector

NASA:

National Aeronautics and Space Administration

NEP:

Nephelometer

NIMS:

Near-Infrared Mapping Spectrometer

ODM:

Orbit Deflection Maneuver

OTM:

Orbit Trim Maneuver

PJR:

Perijove Raise Maneuver

PM:

Propellant Margin

PDT:

Pacific Daylight Time

PST:

Pacific Standard Time

RPM:

Retropropulsion Module

RRA:

Radio Relay Antenna

SSI:

Solid State Imaging

TCM:

Trajectory Correction Maneuver

UTC:

Universal Time Coordinated

UVS:

Ultraviolet Spectrometer

VEEGA:

Venus-Earth-Earth Gravity Assist

Authors and Affiliations

1. Jet Propulsion Laboratory, California Institute of Technology, 91109, Pasadena, CA, USA

   Louis A. D'Amario, Larry E. Bright & Aron A. Wolf

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