Might This Be What You Were Looking For?
I know that somewhere out there, there's a roleplaying campaign that has been waiting patiently, perhaps even without its owner's knowledge, for this website:
Basically, you enter in various parameters for a meteor/asteroid/other object (maybe a Death Star or a Borg Cube?) striking the earth, how far away from the impact you are, and the program calculates the effects of the impact and the effects on you (for instance, is there a fireball big enough to vaporize you and your fancy power armor? ).
Now is the time to create the scenario in your game that will give you an excuse to use this web page!
(Thanks to Science News, always an enlightening magazine, for revealing the Earth Impact Effects Program. And for generally filling my head with fascinating trivia each week, too...)