Nuclear power in space? Petition asks White House to rekindle project – Cosmic Log.

BBC News – Dead stars 'to guide spacecraft'.

Gigantic Aeroscraft Airship Passes Ground Tests, Gets Set For Flight Operations (PHOTOS).

NASA’s NEXT ion drive breaks world record, will eventually power interplanetary missions | ExtremeTech.

BBC – Future – Technology – X-37B: Secrets of the US military spaceplane.