Launched fifteen years ago with technology that was a decade out of date at the time, Galileo discovered the first extraterrestrial ocean, holds the record for most flybys of planets and moons, pointed out a dual star system, and told us about nine more moons of Jupiter.And the brilliance doesn't end there:
Galileo's story is the story of improvisational engineering at its best. When its main 134 KBps antenna failed to open, NASA engineers decided to have it send back images using its puny 10bps antenna. 10 bits per second! 10!
To fit images over that narrow a channel, they needed to teach Galileo some of the tricks we've learned about data compression in the last few decades. And to teach an old satellite new tricks, they needed to upgrade its entire software package. Considering that upgrading your OS rarely goes right here on Earth, pulling off a half-billion-mile remote install is pretty impressive.
As if that wasn't enough hacker brilliance, design changes in the wake of the Challenger explosion completely ruled out the original idea of just sending Galileo out to Mars and slingshotting towards Jupiter. Instead, two Ed Harris characters at NASA figured out a triple bank shot -- a Venus flyby, followed by two Earth flybys two years apart -- to get it out to Jupiter. NASA has come in for an awful lot of criticism lately, but there are still some things they do amazingly well.Score another one for NASA (while you're at it, give Grimmelmann a few points for the Ed Harris reference). Who says NASA can't do anything right anymore? Grimmelmann observes:
The Galileo story points out, I think, that the problem is not that NASA is messed-up, but that manned space flight is messed-up.Is manned space flight in danger of becoming extinct? Is it worth the insane amount of effort and resources we continually pour into the space program? These are not questions I'm really qualified to answer, but its interesting to ponder. On a personal level, its tempting to righteously proclaim that it is worth it; that doing things that are "difficult verging on insane" have inherent value, well beyond the simple science involved.
Manned spaceflight is, in the Ursula K. LeGuin sense, perverse. It's an act of pure conspicuous waste, like eating fifty hotdogs or memorizing ten thousand digits of pi. We do it precisely because it is difficult verging on insane.
Such projects are not without their historical equivalents. There are all sorts of theories explaining why the ancient Egyptian pyramids were built, but none are as persuasive as the idea that they were built to unify Egypt's people and cultures. At the time, almost everything was being done on a local scale. With the possible exception of various irrigation efforts that linked together several small towns, there existed no project that would encompass the whole of Egypt. Yes, an insane amount of resources were expended, but the product was truly awe-inspiring, and still is today.
Those who built the pyramids were not slaves, as is commonly thought. They were mostly farmers from the tribes along the River Nile. They depended on the yearly cycle of flooding of the Nile to enrich their fields, and during the months that that their fields were flooded, they were employed to build pyramids and temples. Why would a common farmer give his time and labor to pyramid construction? There were religious reasons, of course, and patriotic reasons as well... but there was something more. Building the pyramids created a certain sense of pride and community that had not existed before. Markings on pyramid casing stones describe those who built the pyramids. Tally marks and names of "gangs" (groups of workers) indicate a sense of pride in their workmanship and respect between workers. The camaraderie that resulted from working together on such a monumental project united tribes that once fought each other. Furthermore, the building of such an immense structure implied an intense concentration of people in a single area. This drove a need for large-scale food-storage among other social constructs. The Egyptian society that emerged from the Pyramid Age was much different from the one that preceded it (some claim that this was the emergance of the state as we now know it.)
"What mattered was not the pyramid - it was the construction of the pyramid." If the pyramid was a machine for social progress, so too can the Space program be a catalyst for our own society.
Much like the pyramids, space travel is a testament to what the human race is capable of. Sure it allows us to do research we couldn't normally do, and we can launch satellites and space-based telescopes from the shuttle (much like pyramid workers were motivated by religion and a sense of duty to their Pharaoh), but the space program also serves to do much more. Look at the Columbia crew - men, women, white, black, Indian, Israeli - working together in a courageous endeavor, doing research for the benefit of mankind, traveling somewhere where few humans have been. It brings people together in a way few endeavors can, and it inspires the young and old alike. Human beings have always dared to "boldly go where no man has gone before." Where would we be without the courageous exploration of the past five hundred years? We should continue to celebrate this most noble of human spirits, should we not?
In the mean time, Galileo is nearing its end. On September 21st, around 3 p.m. EST, Galileo will be vaporized as it plummets toward Jupiter's atmosphere, sending back whatever data it still can. This planned destruction is exactly what has been planned for Galileo; the answer to an intriguing ethical dilemma.
In 1996, Galileo conducted the first of eight close flybys of Europa, producing breathtaking pictures of its surface, which suggested that the moon has an immense ocean hidden beneath its frozen crust. These images have led to vociferous scientific debate about the prospects for life there; as a result, NASA officials decided that it was necessary to avoid the possibility of seeding Europa with alien life-forms.I had never really given thought to the idea that one of our space probes could "infect" another planet with our "alien" life-forms, though it does make perfect sense. Reaction to the decision among those who worked on Galileo is mixed, most recognizing the rationale, but not wanting to let go anyway (understandable, I guess)...
For more on the pyramids, check out this paper by Marcell Graeff. The information he referenced that I used in this article came primarily from Kurt Mendelssohn's book The Riddle of the Pyramids.
Update 9.25.03 - Steven Den Beste has posted an excellent piece on the Galileo mission and more...