With a jazz band playing in the background and more than a thousand glasses raised, Jet Propulsion Laboratory scientists and engineers said goodbye to one of their own Sunday, toasting the veteran spacecraft Galileo as it performed a dramatic suicide plunge into the giant planet Jupiter.

With Galileo’s gas tank empty after a 14-year space mission, NASA officials decided to destroy the spacecraft to prevent it from accidentally crashing into and contaminating any of Jupiter’s moons.



For the record: For The Record

Los Angeles Times Friday September 26, 2003 Home Edition Main News Part A Page 2 National Desk 1 inches; 63 words Type of Material: Correction

Galileo -- An article in the California section on Monday about the Galileo space probe misstated how closely the craft approached the asteroid Gaspra. It was 1,000 miles, not 1,000 feet. The article also incorrectly stated that Jupiter was 318 times larger than Earth. Jupiter’s mass is 318 times greater than Earth’s. A reference to the craft containing silicone should have read silicon.



The $1.4-billion Galileo was one of the last of the grand NASA missions built at JPL to explore the distant reaches of the solar system.

The stalwart craft had already outlasted its warranty by six years, but surprised its keepers to the end by refusing to go into “safe mode.” It kept doggedly studying Jupiter until it was torn apart and vaporized at approximately noon Pacific time by the intense frictional forces and heat in Jupiter’s violent atmosphere.


“I can’t believe we collected science data all the way in,” said project manager Claudia Alexander, wiping away a single tear. “What a machine.”

Engineers in JPL’s space flight operations center were not able to see Galileo’s destruction or tell exactly when it disintegrated, but they were certain that it was gone. The last signal received from the craft reached Earth at 12:43 p.m. Pacific time -- after traveling through space for 52 minutes.

In a time of turmoil in the manned space program after the destruction of the space shuttle Columbia, the death plunge of Galileo was a chance to recall the good old days of NASA when nothing seemed impossible and heroic rescues were the order of the day.

Hundreds of current and retired engineers and scientists who built, fixed and ran the craft during the nearly 30-year project returned to the Pasadena campus Sunday for one last look. There were hugs, some tears, Jupiter-patterned skirts, a musical tribute set to the Rolling Stones and show tune lyrics and a version of a reality TV show dubbed “Survivor: Jupiter.” The group also remembered 40 of their team members who had not outlasted Galileo.


It was a rare show of emotion at JPL, where engineers consider the stream of robotic offspring they produce their pride and joy but are fully aware they are merely pieces of metal, wire and silicone. Galileo, though, was different.

The 2-ton spacecraft was always JPL’s problem child. It subjected scientists and engineers to crushing disappointments, missed opportunities and innumerable sleepless nights. Despite having a brain less powerful than the average Palm Pilot, the balky craft bloomed to overcome a host of obstacles. It far outlasted its projected lifespan despite the scathing radiation environment that surrounded it.

In eight years circling Jupiter, the craft was able to overturn thinking that the region was cold and geologically dead and revealed two of Jupiter’s moons -- ocean-covered Europa and volcanic moon Io -- as compelling destinations for exploration.

“It’s like the little engine that could,” project manager Alexander said. “Galileo the man, with the force of his personality, changed a lot of opinions. Galileo the spacecraft, by sheer cussedness, did the same thing.”


Galileo was nearly doomed from the start by launch delays that almost put Jupiter out of reach. The spacecraft was supposed to ride into space atop a Centaur rocket in 1982 -- a good year for making the trip to Jupiter because it was relatively close. But NASA officials, in an effort to find work for the space shuttle program, decided to launch Galileo from the shuttle.

The decision meant delays. The 1982 launch slipped to 1984, then 1985 and finally May 1986, when the spacecraft was to be launched along with a rocket that would help propel it to the ever-more-distant Jupiter.

Challenger Disaster

That January, with Galileo awaiting its launch window at Kennedy Space Center, the shuttle Challenger exploded overhead. All shuttle flights were grounded. Galileo was unceremoniously shipped back to Pasadena “without any launch vehicle and no way to get to Jupiter,” said John Casani, a 48-year-veteran of JPL who was Galileo’s project manager at the time.


Launch was rescheduled for October 1989. But with new shuttle safety concerns, the rocket needed to push Galileo the extra distance to Jupiter was banned. It looked like Galileo’s only trip would be to the Smithsonian Institution.

Then, JPL engineer Roger Diehl came up with an idea to slingshot Galileo past Venus and then two times around Earth to pick up enough speed for the trip. The detour would take five years instead of 30 months, but it would work.

The next problem occurred on the way to Jupiter, when Galileo was to open the umbrella-shaped high-gain antenna built to send data and images back to Earth.

The antenna refused to open -- no matter what engineers tried. And they tried thousands of times over three years. It was no use. The antenna was jammed.


Mission managers were left with only a low-gain antenna, a navigational device set at the paltry rate of 10 bits-per-second -- thousands of times slower than a typical home Internet connection. It would take weeks to send a single picture. Scientists were distraught.

Galileo’s transmissions had to be sped up. Programmer Tal Brady was able to send up new commands that tripled the computer’s efficiency. He decreased the signal sent by the spacecraft so more bandwidth could be used for science and compressed data so more could be sent back.

On its journey, Galileo flew within 1,000 feet of the asteroid Gaspra -- the first fly-by and photo shoot of an asteroid. It also flew past asteroid Ida, discovering the orbiting rock had its own moonlet, Dactyl. In July 1994, Galileo had a front-row seat as comet Shoemaker-Levy 9 slammed into Jupiter at 125,000 mph.

In 1995, Galileo was finally approaching Jupiter. Despite being 10 years late, scientists were jubilant. Among the most excited was Rosaly Lopes, an expert on planetary volcanism at JPL hoping to get her first close-up view of the volcanoes of Jupiter’s moon Io.


But then the spacecraft’s data tape recorder broke. Without the recorder working, no data could be saved for transmission to Earth.

Though engineers fixed the tape player, they decided to save it to use later with an atmospheric probe. Lopes would not get her look at the pizza-pie-faced yellow moon after all.

“That was painful,” she said. “I thought my one chance to see Io was done.”

Heading to Jupiter


By December 1995, Galileo was heading to Jupiter. It would buzz within 133,000 miles of the gas giant, a planet 318 times the size of Earth. The interior of Jupiter remains a mystery. Most of the planet is gas and some is probably liquid metallic hydrogen, a state possible only at crushingly high pressure. Scientists suspect that Jupiter’s heart is a rocky core some 10 times the size of Earth.

The gassy planet’s weather is oddly Earth-like. It has storms, winds and hailstones -- only on Jupiter, everything is bigger and more vividly colored. Storms are as big as continents, hailstones as big as trucks. Three-hundred mph winds make Hurricane Isabel look like a kitten. It was into this hellish maelstrom that Galileo’s atmospheric probe dropped.

Galileo’s next stop: Europa.

Scientists had long known Europa was icy and strangely lacking in craters, but it was not until Galileo arrived that they saw ice fractured and piled into ridges and cliffs. The lack of craters meant the ice was fresh. The movement of the ice suggested an ocean lay underneath.


It was an instrument aboard Galileo -- the magnetometer -- that would prove it. By detecting changes in the magnetic field around Europa, a team led by UCLA astronomer Margaret Kivelson found a global layer that could conduct electricity just beneath Europa’s icy surface: a layer of salty water and the first new ocean discovered since Balboa laid eyes on the Pacific.

“Before Galileo, we only had a fuzzy picture of Europa from Voyager. No one quite knew how interesting it was,” Kivelson said.

Galileo’s finding sealed its fate. Because the moon’s frozen ocean could harbor life, scientists decided to crash Galileo into Jupiter to make sure it didn’t accidentally fall into Europa and contaminate it with earthly microbes.

Hopes Answered


Because Galileo remained healthy, mission managers decided to extend the mission for two more years, and then extended it again until this year. The move allowed several more fly-bys of Europa and a second chance to fly past radiation-soaked Io for the still-cautious Lopes.

“I was wary of having my hopes up too high because of the disappointment of the first fly-by,” she recalled.

The Voyager spacecraft had discovered the volcanoes of Io when it flew by the strange, yellow moon in 1979. It counted about a dozen of the spewing vents.

Lopes ended up getting her fly-by -- and more. Galileo survived the radiation and was able to fly by Io seven times. “I had hoped to find one new volcano. In the first observation, we found six,” she said.


By the end of the mission, Galileo had soaked up four times the radiation it was built for and accomplished some 70% of its scientific goals.

Last November, Galileo once again journeyed into the heart of Jupiter’s radiation environment to study the tiny moon Amalthea. Radiation disabled the electronics in the data tape recorder. But engineers were able to perform a long-distance hardware fix, sending current through the circuits to anneal the broken electronics.

“It was one of the most astounding recoveries the spacecraft has made,” said Eilene Theilig, a previous project manager.

The repaired recorder was able to send back data showing that Galileo had detected bright objects circling Amalthea -- a possible miniature rocky ring.


On Sunday’s trip, Galileo collected science all the way to its demise.

It will take some time to decode the data, but the information could confirm the presence of objects or a ring around Amalthea and could tell scientists what molecules are found in Jupiter’s upper atmosphere.

For Galileo, there was no early retirement. The workhorse spacecraft was working until the end.