The Secret of the Ninth Planet

by Donald A. Wollheim

MISSING MEN OF SATURN by Philip Latham—A space crew is held prisoner by froglike men on Saturn

MISSION TO THE MOON by Lester del Rey—Scientists make man's first journey to the Moon

MISTS OF DAWN by Chad Oliver—A space-time machine hurls a 20th-century boy back to 50,000 B. C.

MYSTERIOUS PLANT, THE by Kenneth Wright—A young captive on Planet X prevents Earth's destruction

MYSTERY OF THE THIRD MINE by R.W. Lowndes—Prospecting in the dangerous asteroid belt

PLANET OF LIGHT by Raymond F. Jones—A trip to another planet shows how the universe can be saved from destruction

ROCKET JOCKEY by Philip St. John—A space pilot battles Martians in rocket race

ROCKET TO LUNA by Richard Marsten—A stowaway on a Moon-bound rocket proves his worth

ROCKETS TO NOWHERE by Philip St. John—Scientists establish a colony on the Moon

SECRET OF THE NINTH PLANET, THE by Donald A. Wollheim—A high-school senior investigates the theft of the solar system's light