Thanks for that Alex,
I too am very much into the science side of our hobby, it just keeps my mind thinking. I like the bit about how fast dark matter falls, sounds like testing out the old apple falling out of the tree as done by Newton to discover gravity, maybe the inhabitants of the dark matter planet could see if the toast that they cooked for breakfast and then falls off the side of the kitchen table would land butter side up,only problem on the dark matter planet both sides of the toast would be burnt black.
on a more serious note thanks for the link to these sites.
Matt.