Talk:BB-8/@comment-70.173.165.164-20160311211941/@comment-27666888-20160312011038

From the errata: "A ship cannot perform a barrel roll if this would cause its base to overlap another ship or obstacle token, or if the maneuver template overlaps an obstacle token."

So if you've landed in a way that leaves half of your base hanging off the asteroid, you can BB-8 in that direction, but not in the direction which would see the barrel roll template overlap the asteroid.