[KenWittlief]

since the universe is expanding and our solar system is hurtling through space at thousands of miles per hour

wouldnt a time traveller also need a star ship? you send yourself even one hour into the future, and the earth will no longer be at this location when you pop back in

someone travelling from hundreds or thousands of years in the future would need to travel light years to get back to where we are now, relative to the center of the universe.

still the idea of only having one time travel convention is a little presumptuous - why not have one every 100 years?

I can see people in the future saying "you wanna goto that 2005 convention?"

"nah, the weather was miserable, besides theres nothing to do in Boston in 2005 - lets goto the 2805 one next"