‘You Didn’t Prepare Me’: Remembering America’s Galileo Mission to Jupiter, 30 Years On (Part 2)

Aerial view of Atlantis’ rise to orbit on 18 October 1989, 30 years ago this week. Photo Credit: NASA

Thirty years ago, this week, shuttle mission STS-34 and the crew of Atlantis roared aloft from Pad 39B at the Kennedy Space Center (KSC) in Florida to deliver NASA’s Galileo spacecraft onto the first leg of its long odyssey to Jupiter. As outlined in last weekend’s AmericaSpace history feature, the mission had been subject to lengthy delays, caused by political and technical issues—including the January 1986 Challenger tragedy—and was also adversely affected by anti-nuclear protesters campaigning against Galileo’s plutonium power unit.

Finally, after two false starts, Commander Don Williams, Pilot Mike McCulley and Mission Specialists Franklin Chang-Diaz, Ellen Baker and Shannon Lucid strode out from their crew quarters on the morning of 18 October 1989 to begin a mission which would revolutionize our understanding of the Solar System’s largest planet.

The STS-34 crew in the shuttle simulator. From left to right are Pilot Mike McCulley, Mission Specialists Shannon Lucid, Franklin Chang-Diaz and Ellen Baker and Commander Don Williams. Photo Credit: NASA

The astronauts had been training for STS-34 for almost a year. Williams flew previously as pilot of Mission 51D in April 1985, a voyage which deployed two communications satellites and featured the first unscheduled session of Extravehicular Activity (EVA) in the shuttle program. Lucid was a veteran of the multi-national Mission 51G in June 1985 and Chang-Diaz had flown on Mission 61C in January 1986, which returned to Earth only ten days before the loss of Challenger. For their part, McCulley and Baker were making their first space missions. Liftoff on 18 October was delayed by 3.5 minutes, in order to update Atlantis’ computers for a change in the Transoceanic Abort Landing (TAL) site—which had been relocated to Zaragoza in Spain, due to heavy rain at Ben Guerir in Morocco—and the shuttle speared for the heavens at 12:53 p.m. EDT.

The sheer dynamism of launching into space surprised McCulley, who later described the effect as primarily “acoustic”, creating a sensation that “shakes your body and your soul”. At one point in the ascent, after Atlantis cleared Pad 39B’s tower much faster than his months of simulator training said it should, McCulley turned to Williams and quipped: “You didn’t prepare me for this!” Also unexpected was the quick-fire separation of the two Solid Rocket Boosters (SRBs), a couple minutes into flight. “In the simulator, there’s a flashbulb that goes off when you get to SRB sep,” McCulley told the STS-34 post-flight press conference, “and in real life there’s an explosion that goes off, right in front of your face. It was wonderful. But it was surprising!”

Saddled with the burden of command, for Don Williams STS-34 carried unique responsibilities. Photo Credit: NASA

In fairness to Williams, commanding this mission was quite dissimilar to piloting his previous one. “There’s some amount of loneliness at the top,” he told the NASA oral historian, “and having that authority and with it comes the responsibility for accomplishing the mission. With those first two comes the most important one, in my mind, which I learned early on as a midshipman at Purdue: With the authority and responsibility comes the accountability and, if something goes wrong, it’s not somebody else’s fault, it’s the person in command’s fault. The same thing is true when you command a mission. You’re accountable for the performance of the crew, for the accomplishment of the mission, for getting the objectives completed successfully and for getting the spacecraft back so somebody else can use it again. That’s the name of the game.”

Six hours after liftoff, at 7:15 p.m. EDT, under the watchful eyes of Lucid, Galileo and its attached Inertial Upper Stage (IUS) booster were tilted to the deployment angle and set free. “Galileo is on its way to another world,” radioed Williams. “It’s in the hands of the best flight controllers in the world. Fly safely.” For physicist Chang-Diaz, seeing the spacecraft depart into the inky blackness of space brought his childhood dream of visiting other planets flooding back. Soon after deployment, Williams and McCulley maneuvered the shuttle to a safe separation distance and the IUS engine was ignited to boost Galileo out of Earth orbit and onto a course for Venus, then two flybys of Earth, all of which would be utilized to pick up a gravitational shove to reach Jupiter in December 1995.

Mounted atop its Boeing-built Inertial Upper Stage (IUS), Galileo parts company from Space Shuttle Atlantis on the evening of 18 October 1989. Photo Credit: NASA

“Both Ellen and I sighed a great sigh of relief, because we figured Galileo was not our concern at that point, because we’d gotten rid of it,” Lucid said later. “Happiness was an empty payload bay and we got happier and happier as the IUS and Galileo went further away from us.”

As circumstances transpired, it would remarkably demonstrate the triumph of human ingenuity over adversity. Eighteen months into its cruise, and several months after its first flyby of Earth, in April 1991 Galileo’s high-gain antenna only partially unfurled, threatening to ruin the mission. “Workaround” techniques were devised to use the low-gain antenna instead, and the spacecraft returned remarkable images from the asteroids Gaspra (in October 1991) and Ida (in August 1993) and, far from conducting two years of scientific exploration at Jupiter, Galileo spent almost eight years in operation. During that period, it measured the chemical composition of the giant planet’s atmosphere, directly observed its ammonia clouds and mysterious Great Red Spot, analyzed the causes and effects of volcanism on Io, yielded tantalizing clues for liquid oceans beneath the frozen surfaces of Europa and Ganymede and mapped and modeled for the first time the extent of Jupiter’s gigantic magnetosphere. On its way to the planet, in July 1994, Galileo also observed the impact of Comet Shoemaker-Levy 9 into the Jovian clouds.

Having set Galileo on its way, the primary mission of STS-34 was over. Several secondary experiments were performed, including the first flight of the Shuttle Solar Backscatter Ultraviolet (SSBUV) instrument in the payload bay. This was part of an ongoing NASA effort to calibrate ozone sounders on free-flying satellites and verify the accuracy of atmospheric ozone and solar irradiance data. A polymer solidification study ran on the middeck and observations were made of lightning events in the high atmosphere.

Atlantis lands at Edwards Air Force Base, Calif., on 23 October 1989. Photo Credit: NASA

Living in space for five days was carried its own idiosyncrasies. Williams likened it to a camping trip, with the exception that none of them departed their camper van for the entire five days. “What’s it like to be in space?” he rhetorically asked his audience at the STS-34 post-flight press conference. “Unfortunately, this is one of the most difficult questions to answer, since the word “like” implies a comparison, and it’s not “like” anything you’ve ever done before. So most of us are stuck with describing the differences. How do you describe weightlessness, when we live in a world where everything weighs something? The ability to move about, almost be thinking about it. No up or down. Behavior and misbehavior of common, ordinary things, such as liquids, elastic, food, objects.

“Watch the video with us,” Williams invited his audience. “Compare it to things you do on Earth. Look for the differences. Perhaps you can describe ’em to us!”

Amid this weightless wonderland, the astronauts were periodically drawn away to tend to minor technical issues with Atlantis herself. A problem with one of the shuttle’s Auxiliary Power Units triggered an alarm on 22 October, as did a glitch with the Flash Evaporator System and cryogenic oxygen manifolds. Predicted high winds at Edwards Air Force Base, Calif., on the 23rd prompted a decision to bring the shuttle home two orbits earlier than planned, and Williams and McCulley guided Atlantis to a smooth touchdown at 6:33 a.m. PDT (12:33 p.m. EDT), just 20 minutes short of five full days after launch.

Don Williams regarded STS-34 as having accomplished something quite remarkable for science. “We knew that Galileo was going to be a lasting program,” he said. “The Galileo mission, we knew, if it was successful, the spacecraft was going to end up in orbit around Jupiter several years later and then there were going to be several years of data and images sent back. It was going to be a living, ongoing program and we got to be a part of it.”

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