1. Introduction

In just less than fourteen months, on December 7, 1995, Galileo will arrive at Jupiter completing its over six-year circuitous interplanetary journey. Even though there is a bit more than a year to go, Galileo has already traveled over 90% of its interplanetary path length as indicated in Figure 1.

Figure 1

An overview of flight activities performed this calendar year and those required between now and arrival is provided in Figure 2. These activities and preparations for them are the subject of this Paper. All high-priority asteroid Ida data was returned in spite of some new challenges. The most delightful challenge stemmed from the first-ever discovery of an asteroid satellite. In July, Galileo performed observations of Comet Shoemaker/Levy-9 (SL-9) fragment impacts on Jupiter. Due to its unique vantage point in space, only Galileo's "telescopes" could see the impact region when the impacts were occurring. Some excellent impact observations have already been played back to Earth and the balance of the feasible return will be completed by early 1995.

Figure 2

The Atmospheric Entry Probe will be checked out in March 1995, following the loading of the new arrival phase flight software in the Orbiter (Ref.1). The Orbiter is now scheduled to release the Probe on July 13th. Seven days later, on July 20th, the Orbiter 400N main engine will be used for the first time to deflect the Orbiter to its Jupiter aim point. Five months later, both vehicles arrive at Jupiter as illustrated in Figure 3.

Figure 3

The Orbiter performs a 1,000 km altitude gravity-assist flyby of Io and then subsequently overflys the descending Probe (Fig. 4a) to gather the Probe data via the Relay Link for 75-min. About an hour after the Relay, the 400N engine will burn for nearly an hour to place Galileo into Jupiter orbit.

Figure 4a

The Orbiter's two-year primary mission satellite-gravity-assist orbital tour of the Jupiter System (Ref 2) is illustrated in Figure 4b. Figure 1 shows when each Orbiter perijove pass/satellite encounter occurs and the corresponding position of Jupiter for each. References 1 through 4 provide comprehensive descriptions of the Galileo mission, spacecraft, and science payload. The spacecraft health and performance continue to be excellent. All the new capabilities in development to perform the mission with the Low Gain Antenna (LGA) (Ref.1) are on schedule and will meet and in many cases exceed original expectation .

Figure 4b