Variety (via NY Mag's Vulture) has the news:
ABC has decided to end the show after a single year -- but in an unusual move, the net will keep the show on the air through the end of its full run.
That will give the series a rare opportunity to sign off with a proper finale, wrapping up the series' core mystery.
Network insiders said they were fans of the show and pleased with its creative chops -- but that the ratings ultimately didn't warrant a second season. The most recent seg of "Life on Mars" averaged just a 2.0 rating/5 share among adults 18-49, as well as 5.5 million viewers.
The show had been filmed, in part, around the neighborhood going back to last summer. We liked the premise -- time-traveling cop returns to 1970s NYC. And we championed the show until we actually watched it. Oh, it was fine. But I stopped watching after the second or third episode.
Here's our complete "LIfe on Mars" coverage.