An artist's depiction of Maldek
Maldek was once the home planet of the Atlanteans before King Ghidorah ravaged it and turned it into a lifeless husk. Based on what is known about the Atlanteans, one can assume it was a primarily aquatic planet with scattered land masses of tiny size before its devastation. The location of Maldek in the universe is being searched for by archaeologists studying the ruins of Atlantean cities so that probes can be sent to photograph the planet and see what it's current state is.