The Tenth Planet?
- Episode aired May 24, 1972
Patrick Moore explains why Planet X has been so difficult to detect, and what kind of place this dim, cold world at the limits of our solar system would be.Patrick Moore explains why Planet X has been so difficult to detect, and what kind of place this dim, cold world at the limits of our solar system would be.Patrick Moore explains why Planet X has been so difficult to detect, and what kind of place this dim, cold world at the limits of our solar system would be.