Space travel hoax
| Some dare call it|
|What THEY don't want|
you to know!
Various "reasons against" are provided:
- Cosmic/solar radiation.
- Issues with temperature.
- Rockets must push against air, so they cannot work in vacuum. How ejecting combustion products one way without pushing the rocket in the other satisfies conservation of momentum is beyond explanation (simple answer: it doesn't).
-  Anders Björkman of Heiwa Co thinks that human space travel is not possible, and also that nuclear weapons are a similar hoax.
-  and  The Freemasons are in on it!
-  Unsurprisingly, such beliefs can be found at Above Top Secret.
-  Another example from CluesForum.