Elon Musk claims that, using fully reusable hardware, the cost of launching payloads to space could eventually go as low as $10 per pound. Other low-cost proposals for putting payloads into orbit have ...

They call it a "scramjet," an engine so blindingly fast that it could carry an airplane from San Francisco to Washington, D.C., in about 20 minutes -- or even quicker. So fast it could put satellites ...

Going really fast has always been one of the major goals of air-breathing aircraft ("air-breathing" meaning that it's not powered by a rocket, and relies on air for fuel combustion) development since ...