This post is in regards to the Institute for Creation Research’s September 6, 2003 program about Comets. You can listen to the audio here.
Even though this episode of ICR radio was produced before my previous post on comets and creationism, I’ve opted to write about it second because the claims in it are more subtly incorrect.
The first comment on this episode is really more of a nit-pick (@ 4 min): The scientist on the program claims, “The famous Shoemaker-Levy  comet, which broke up into 9 pieces and crashed into the surface of Jupiter …”
Now this claim really isn’t used to try to prove creationism, but another purpose of this blog is to help propagate good astronomy when there is bad astronomy being stated. There are two problems with the above statement. The first is that the comet in question did not break into 9 pieces, but rather it broke into 21 main fragments, labeled A through W. Also, Jupiter really doesn’t have a “surface” in the traditional sense. It may have a rocky core, but we don’t know that for certain. What we do know is that its atmosphere is huge, extending at least 5 times Earth’s radius, and the comet fragments that crashed through the jovian atmosphere would have been crushed by the pressure well before they reached any “surface.”
About 6 min 30 sec into the broadcast, we get the first bit of real pseudo-astronomy: One of their scientists is talking about how comets tend to fragment, they lose some of their material during their orbit, and they’re somewhat fragile if they come really close to a large, massive object (like a planet or star). But he then states, “This has been a problem for evolutionists for a long time because comets just don’t last, and they certainly don’t last over the supposed age of the solar system.”
Again there’s that “evolutionist” label … somehow because I’m an astronomer who uses “real” science I’m now an evolutionist, too. Regardless of this snub, this is the same argument that I talked about in my previous post on comets: Comet nuclei were not all “launched” into close-Sun-passing orbits at the beginning of the solar system. They effectively “lie in wait” in the frigid outer regions until they collide amongst themselves or a passing massive body causes their orbits to change, bringing a few into the inner solar system. This effectively sets their internal “clocks” at a zero-age in terms of losing material, and so it really has nothing to do with “proving” the solar system was created a matter of a few thousand years ago. This is NOT “good evidence that the Universe isn’t billions of years old,” as the narrator states.
The next argument is closely related (about 7 min 45 sec in): Dr. Ross Humphreys is a physicist for the ICR and says, “There’s (sic) some comets called ‘short-period comets’ that come around so frequently that they could not have been in our solar system longer than 10,000 years. … Halley’s comet is acknowledged by scientists to not have been in the solar system longer than 90,000 years.” (emphasis mine)
So this is the same argument as above which I’ve already addressed. However, there’s a new wrinkle. This person claims that these comets aren’t even in the solar system until recently. This simply doesn’t make sense. People who do modeling have shown that it’s nearly impossible to have objects line up just right such that two bodies that were not gravitationally bound to begin with (a comet being “in” our solar system, in other words) can be captured. I believe their physicist meant to say “in the inner solar system,” which could be more correct. But this is a pretty obvious mistake to make, and if you’re going to make an argument from authority (the guy being a physicist) you would hope their authority knows that comets didn’t magically appear from beyond the solar system.
There are a few more misstatements and fallacious arguments in the next few minutes episode, but they are pretty much the same as those I have addressed below and in my other comet post (not believing in the Oort Cloud simply because they can’t see it). Oh, and apparently I’m now a “Big Bang Theorist” because I know about comets and agree with the evidence supporting the Kuiper Belt and Oort Cloud. Maybe I could write a grant to NASA to study comets because I’m a Big Bang Theorist.
The last argument they make that I want to address is the claim the Kuiper Belt “can’t” be a source of short-period comets (about 10 min into the program). The evidence they point to is that the objects in the Kuiper Belt are generally redder in color than comets. They claim this means they’re two entirely different classes of objects, and that evolutionists (honestly, how the heck do they equate studying comets with being an evolutionist?) have tried all sorts of ways to get Kuiper Belt Objects (KBOs) to “lose” their red.
This is actually a fairly easy problem. Without getting into chemistry, spectroscopy, and physics, the basic idea is weathering. Even though there’s no air, water, etc. in space, there are particles that are constantly interacting with KBOs, and those particles mainly come from the solar wind. They have the ability to chemically alter the material they come into contact with, but only the very upper surface. When the objects are weathered, they become redder. Once a KBO is nudged into a sun-grazing orbit, however, the crust sublimates (turns from a solid directly into a gas). What is sublimating? The upper surface of the KBO … the surface that was weathered. So after a first-close-pass with the Sun, the object can easily lose that red color and look like an ordinary comet.
A final comment goes to the nature of science. On this program, as on the comet one I discussed below, the fall-back is something to the effect of, “Creationism has a much simpler answer than all this Oort Cloud, Kuiper Belt, and other stuff. It’s that the Solar System was created by God recently.”
That is faith. Plain and simple. It is NOT science. Science makes testable, potentially falsifiable hypotheses about the way things work. If you pass everything off to God as your explanation, that is perfectly legitimate faith, but it has nothing to do with science because it is not testable nor falsifiable. The explanations I have given may seem “materialistic,” but that is the nature of science; by definition, it does not accept faith-based explanations.
And I must add that, so far, the materialist explanation has worked perfectly fine for explaining the apparently unexplainable features of comets.