Activity for Scott Whitlock‭

Type	On...	Excerpt	Status	Date
Answer	—	A: Can there be a space age without petroleum (crude oil)? The other answers are good so far, but I don't think anyone has pointed out that there's another way to easily lower the difficulty of getting off an alien planet: just reduce the gravity and/or atmospheric density. A smaller planet with less atmosphere is significantly easier to take off from. E... (more)	—	over 7 years ago