The Secret of the Ninth Planet
- First published
- 1959
- Reading level
- Plain English
- Price
- Free
About the book
"The Secret of the Ninth Planet" by Donald A. Wollheim is a science-fiction novel published in 1959. When the Sun's light mysteriously begins to dim across Earth, threatening a new ice age, young Burl Denning discovers alien machinery in the Peruvian Andes. As calculations reveal the Sun may explode within years, Burl joins a desperate expedition aboard an experimental antigravity spaceship to hunt down similar installations throughout the solar system and confront an alien force from Pluto.
- Science fiction
- Pluto (Dwarf planet)
Updated September 2026. Public domain in the USA. Text and summary from Project Gutenberg eBook #33644. The Secret of the Ninth Planet on Wikipedia.
