Much of what is being observed can be easily explained. I am not an astronomer nor a physicist, but if you think about what is going on, it makes
sense. Hopefully I can explain it without being confusing.
Imagine being in a car on three lane highway. You are traveling at 65 miles per hour on the inside lane along a very long, gentle curve. About 1 mile
ahead of you is an old beater of a car driving in the outside lane at a speed just slightly slower that you.
Note that if you were to stop your car, the other car is moving away from you. The other car is also moving away from you when your car is moving at
65 miles per hour. However, because it is moving SLOWER than your car, it appears that to be coming at you very slowly. As your car catches up AND
continues to travel the inside lane (thus adding to your cars progress in catching up), you will eventually pass the other car.
This is the same with the comet. Our position has been such that we are catching up to the comet, but at the same time it is moving away from us. The
curvature of our orbit around the sun is always inside that of the comet. As we continue moving around the sun it will become clear that Earth and the
comet are not on a collision course.
Moving on... since it is evening the other car has it's headlights on. Because the other car is almost straight ahead of you, the headlight beams are
hardly visible.
Again, this is what is happening with the comet. A comet's tail is always pointed AWAY from the sun, regardless of the direction that the comet is
traveling. Our current position in relation to the comet and the sun has us sitting in such a way that we are between the two bodies. So the tail of
the comet is pointing almost directly AWAY from us. Therefore that tail appears to be very minimal or, in some observations, non-existent.
Lastly, there is the matter of the seemingly increasing size of the comet or at least the debris cloud that it left behind. Taking this back to the
car example, imagine that the old junker car ahead of you suddenly backfires loudly and issues a big, nasty puff of thick, black smoke that lingers
heavily as you approach. The other car is still moving away, but the smoke does not travel with the same speed as the car. Meanwhile, as your car is
still moving, the puff of smoke gets bigger and bigger as you approach it.
That's quite possibly what we are seeing with this comet. Assuming that something took place and the comet threw up a big cloud of dust, most likely
that dust is not moving at anywhere near the same speed as the comet itself. So, because we are moving at a course that makes the comet appear to be
"ahead" of us, the cloud of dust will also appear "ahead" of us. As we move toward the comet and it's dust, the dust will look like it is getting
bigger and that we're going to go right into it. However, as the curvature of our orbit begins to take us away from the comet, so to will it take us
away from the dust cloud. Both of them will begin to grow smaller.
I hope that makes sense. It is not always easy to put into words a concept that is very clear in thoughts.
[edit on 7-11-2007 by John_Q_Llama]
[edit on 7-11-2007 by John_Q_Llama]