Gravitar (1982)

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. In the side-view levels, the player has to destroy red bunkers that shoot constantly, and can also use the tractor beam to pick up blue fuel tanks. Once all of the bunkers are destroyed, the planet will blow up, and the player will earn a bonus. Once all planets are destroyed, the player will move onto another solar system.