I'm trying to collect all of the gold bricks in the game but am missing two. They are both space battles above the planets of Maridun and Ryloth. When i get there though, I cannot find the starting gold brick to shoot and start the missions. I have completed the majority of the game so I don't think I have to do something else first. I have done both Ground **** missions on these planets, destroying ships and debris in space even tried the gun turrets. What am I missing?