Galileo Probe Entry Timeline

Probe Entry was December 7, 1995!

The Galileo Probe became the first atmospheric probe to examine a gas giant on 7 December 1995. The key events which occurred were (all times are the time of the event at the spacecraft given in Eastern Standard Time):

Time             Event
________         _____
11:04 a.m.       Coast timer initiates probe operation

12:46 p.m.       Orbiter flyby of Io (~1000 km) (No imaging or spectral data

 2:04 p.m.       Energetic Particles Investigation (EPI) begins measuring
                    trapped radiation in a region previously unexplored.

 4:54 p.m.       Galileo Orbiter reaches closest point to Jupiter

 5:04 p.m.       Probe entry and data relay

 5:05:52 p.m.    Pilot parachute deployed

 5:05:54 p.m.    Main Parachute deployed

 5:06:02 p.m.    Deceleration module jettisoned

 5:06:06 p.m.    Direct scientific measurements begin

 5:06:15 p.m.    Radio transmission to orbiter begins

~5:08 p.m.       Visible cloud tops of Jupiter reached

 5:12 p.m.       Atmospheric pressure the same as Earth's sea-level pressure

 5:17 p.m.       Second major cloud deck is encountered (uncertain)

 5:28 p.m.       Water clouds entered (uncertain)

 5:34 p.m.       Atmospheric temperature equal to room temperature on Earth

 5:46 p.m.       Probe enters twilight

 6:04 p.m.       End of baseline mission. Probe may cease to operate due to
                     lack of battery power, attenuation of signal due to
                     atmosphere, or being crushed.

 6:19 p.m.       Orbiter ceases to receive probe data (if still transmitting)

 7:27 p.m.       Ignition of Galileo main engine (49 minute duration) to
                     insert into Jovian orbit

It is estimated that by 3:00 a.m. (EST) on 8 December 1995, the probe had been completely vaporized by the heat in Jupiter's atmosphere.

A more detailed version of this timeline is available from Ames Research Center

| NSSDCA Galileo page | NSSDCA Planetary page |

Dr. Edwin V. Bell, II
Mail Code 690.1
NASA Goddard Space Flight Center
Greenbelt, MD 20771

NASA Official: Dr. David R. Williams V1.0, 14 June 1996
Last Updated: 07 February 2002, EVB II