The thing with nasa is that when they use money to build and land things such as space rovers or space shuttles, the money that is used is put back into the economy instead of just floating in space. So the idea that its a waste could easily be debunked by the fact that the money that is used is still in the economy, whether or not you believe the exploration of space is needed could also be a solid point for your paper. Hope that I could help, Good luck with your paper