Since its premiere when it actually finished ahead of “Eleventh Hour,” the ABC series “Life On Mars” is experiencing a little bit of a boost in the ratings, experiencing some of its best numbers in weeks Thursday night. “Life On Mars” earned a 5.7 rating/10 share, finishing just behind “ER” on NBC, but a good distance behind “Eleventh Hour,” which earned a 7.7/13, according to Fast National ratings from Nielsen Media Research. Those numbers were up more than 5 percent from the previous week, but is still more than 6 percent off its average after four episodes. It’s down more than 42 percent from its “Grey’s Anatomy” lead-in, but finished slightly better than “Ugly Betty” in the 8 p.m. hour for ABC. “Eleventh Hour” is still working very strong, and in fact was the top genre …