Galileo’s Space Odyssey
When Stanley Kubrick’s movie “2001: A Space Odyssey” was released in 1968, that date seemed as far away as the odyssey’s destination, the planet Jupiter. But now that many of us have driver’s licenses good until well into the next millennium, 2001 no longer seems so distant. Nor, after NASA’s exhibition of the latest photos from its probe Galileo, does Jupiter.
In “2001,” Jupiter was depicted less as another planet than as another time-space dimension: a roiling, thundering collection of red, brown and white jet streams wherein one astronaut, as director Kubrick explained, “ascended from ape to angel.” Since Galileo’s photos began streaming in last December, however, the planet has proved less surreal. Surprisingly like our own sun, Jupiter seems to be composed almost entirely of hydrogen and helium. These data have led many scientists to embrace the theory that Jupiter is a star that never got big enough to ignite, and to distance themselves from the earlier notion that Jupiter is basically a rock like Earth that sucked in surrounding gas.
Galileo’s most recent photos of Jupiter’s giant satellite Ganymede, released last week by NASA, offer an even more familiar sight: fissures, wrinkles and furrows that look uncannily like the San Andreas fault. Scientists say these features were probably generated by the kind of geologic activity that causes quakes on our planet. But while on Earth these clues to seismic behavior were largely erased by subsequent geologic stretching, compressing and folding, they remain relatively pristine on Ganymede.
Galileo’s visit to Ganymede has also posed many questions scientists cannot begin to answer. For instance, why does this strangely frigid world, where volcanoes belch snow, possess a magnetic field--a force that is found around other planets only when there are hot fluids carrying an electric charge?
Unquestionably, the odyssey of Galileo underscores the value of persistence. Nowhere has the astronomical adage “the space game is a waiting game” been brought home more clearly than by the problem-plagued spacecraft. First, its launch was delayed three years by the explosion of the space shuttle Challenger. Then in 1991, two years after its launch, its main communications antenna failed to unfurl (it remains only partly open).
Nevertheless, by reprogramming the software--”you might say we had to perform a complete brain transplant,” quipped one of its designers--Pasadena’s Jet Propulsion Laboratory managed to get the spacecraft in shape to meet about 70% of the original goals. “The lesson,” said Galileo project manager William O’Neill, is that “if you never give up, you can make anything work.”
