Mystery in Space #9

In "The 24,000-Hour Day!", two men take a job mining on an asteroid where a single day stretches on for 24,000 hours—long enough to make a thousand dollars a day seem like a bargain, but far too long to ever truly escape.

In "The Menace of the Alien Test Tubes!", a mysterious missile from beyond the stars crashes to Earth, carrying four enigmatic test tubes filled with alien chemicals that spark unpredictable and perilous reactions. The arrival sends shockwaves through the scientific community, as two researchers find their own groundbreaking invention suddenly overshadowed by the extraterrestrial threat.