I'm putting together a homebrew adventure for a space horror game (using the Aliens RPG ruleset) and I was thinking about what a world with Mars like mass and lack of volcanic activity and ozone layer be like at a Venus like distance from the sun. Would/could such a world still have the very thin Martian atmosphere? Given such a thin atmosphere and a close sun would it be right to think there would be a great difference in night to day temperature, especially if the planet had an Earth-like period of rotation? Would this drive a very stormy climate (of course the thin atmosphere might make this quite different to storms on Earth)? What other features should there be on such a world?