I was a computer programming kid in HS so when my freshman year at college I went to an observatory and they had a moon lander simulation running I had build my own. Having no background in physics I guessed at the math. I think I did it in gwbasic or maybe pascal as well. At any rate had a decent version going in a couple days. Wish I still had it. All my computers and disks were stolen while they were in storage so I lost all my old code from that era. At any rate wanted to say nice game!