A new experiment showed that humans may be able to reproduce in space, paving the way for self-sustaining colonies.

Sperm may lose their ability to navigate in microgravity, raising new questions about whether human reproduction is possible in space.

Knowing up and down seems key for sperm to reach an egg.

The central premise of the blockbuster film “Project Hail Mary” is a long-shot mission with a familiar goal: Save humanity ...