Super DC Giant #27

An alien work crew comes to earth and starts leveling buildings, but it's all for the purpose of saving Earth. The aliens know that a white dwarf star is on a collision course with Earth so they want to mount a cannon to deflect the star from its path. But they miss. Earth's last chance is Rick Jordan, who's invented the Graviton, a device that can create a temporary zero gravity field and allow Rick to plant explosives on the dwarf star.