Wakusei Daikaiju Negadon

A world of the future, madly over populated, searches for a new home on Mars to help support humanity. After terraforming Mars into a habitable landscape a Japanese ship returning from the planet crash-lands on a Tokyo street, unleashing a terrible monster. The only man who can stop Negadon is Dr. Narasaki, and his robot Miroku...

(Source: Anime News Network)