Intelligently Designed? Chaos and Catastrophe in our Solar System
Stephen Battersby explains in New Scientist (June 13, 2009) that planetary orbits which appear to be regular and reliable are actually quite unstable in the long run because, over time, tiny gravitational interactions can add up in ways that we cannot predict — and which might lead to catastrophe:
Mercury is the key to catastrophe. It is especially susceptible to Jupiter’s influence because of a small celestial coincidence: Mercury’s perihelion, the point where it gets closest to the sun, slowly moves around at a rate of about 1.5 degrees every 1000 years, and Jupiter’s perihelion moves around only a little slower. One day, the two will probably fall into sync, at which time Jupiter’s incessant gravitational tugs could accumulate and pull Mercury off course.
A study led last year by Jaques Laskar of Paris Observatory in France found a slim chance that Mercury’s orbit could be pulled into a highly elongated ellipse, putting it on a potential collision course with Venus. That work used a mathematical trick to calculate average changes over many planetary orbits, so the method was limited. “Close to a collision, it loses its validity,” says Laskar. He and his colleague Mickaël Gastineau have taken a more thorough approach by directly simulating 2500 possible futures, calculating the planets’ orbits over 5 billion years, up to when the sun turns into a red giant.
In some of those simulations, Mercury's orbit goes so wrong that it plunges into the sun or even slams into Venus. Before that happens, though, Mercury's orbit would cause its gravitational field to affect other planets, causing them to start going out of control as well. In one simulation, Mars end up colliding with the Earth; in another it merely passes close to Earth — but close enough that our gravity pulls the Red Planet apart, leading it to fall on us in pieces. Other simulations have all the inner planets shifting about, colliding with each other or just moving to new, irregular paths.
The notion that nature operates like clockwork is one that can be traced back to the earliest days of modern science and the modern era — once humans started to build clocks and clockwork machines, they started to assume that nature itself was constructed by God in a similar manner. Put another way, humans concluded that nature works in much the same manner as anything we ourselves build. This ignores the fact that we have much greater limitations on what we can build than exist on nature as a whole -- or that would exist for a deity.
Nature doesn't operate like clockwork. It only appears to because there are regularities which work consistently over long enough spans of time that we humans conclude it must always be so. In reality, there are small, subtle irregularities which we can't observe very readily and which lead to chaos without our recognizing it — at least until it's too late. What we think of as "intelligent design" is just a set of favorable circumstances which we have grown accustomed to and which won't necessarily persist.
This, then, is a key difference between religion and science: religion tells comforting tales about how the universe is set up for our comfort and convenience while science reveals the truth that things in the universe are more hostile, unstable, and dangerous than we previously assumed. Religion tries to comfort, even if that requires lies; science tries to tell us the truth, even if it discomfits. Which you prefer says a lot about what sort of person you really are.
But, but, but, it’s all part of God’s plan! How are we to understand His plan anymore than an ant could understand our plans? Maybe these possibilities are God’s way of motivating us. Or it could be Satan’s work. No, wait, it’s punishment for giving that lesbian her TV show instead of stoning her to death.
Austin Cline:
When asked about where this evidence is, they will cite examples of they say is “fine tuning” in the universe — like how our solar system is set up so that Earth is right in the zone where life can exist.
Obviously our planet and its orbit would appear to be fine-tuned, because if they were any different, we wouldn’t be alive, and thus couldn’t make an argument from design.
When I became an avowed atheist several years ago following decades of strong doubt, I began to take an interest in astronomy, part of my desire to learn as much as possible about our galaxy while I still have the mental capacity to absorb it.
I do not, by any means, claim to be an expert on the subject, but I have learned enough to realize that we are literally sitting on a time bomb, which more than ever points to the chance and randomness of our evolution.
The Sun, eventually, will prove too hot for us, but not for another 500 million to one billion years, scientists tell us, so apparently we’re safe for the time being, however, in my book, nothing is guaranteed.
One false move somewhere in the universe could spell disaster, and the universe is anything but ordered, constant or stable.
The best we can say at the moment is: “So far, so good!”
Whatever happens to the universe, or our own galaxy, those living today are not likely to be around when the eventual disaster occurs. That’s the good news!
The world isn’t supposed to last 500 million years, it just needs to last until the Rapture ™.