Gravitar

Gravitar is a color vector graphics arcade game released by Atari, Inc. in 1982. The player controls a small blue spacecraft in a fictional solar system with several planets to explore. If the player moves his ship into a planet, he will be taken to a side-view landscape. Unlike many other shooting games, gravity plays a fair part in Gravitar: the ship will be pulled slowly to the deadly star in the overworld, and downward in the side-view levels.