ABC canceled its time-traveling cop show Life on Mars last night due to crappy ratings. The show will air through the end of its first season — apparently ABC doesn't have anything to replace it with right now. [Variety via Vulture]In terrible news, one of the 3 or 4 TV shows I actually make an effort to watch every week has been canceled. On the upside, I will only have one season of DVDs to buy, sort of like Firefly. Why do all (only?) the good shows die young?