Elon Musk’s SpaceX suspects a fire is to blame for his 400-foot-tall ... oxygen fuel may have built up pressure in the colossal rocket’s cavity during liftoff and sparked a fire.

The Federal Aviation Administration is requiring Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin to investigate what went wrong on their respective mega-rocket test flights this week.

On Thursday, Bezos' Blue Origin company launched its big rocket, called New Glenn. It lifted off at 2:30 a.m. ET from Launch Complex 36 at the Cape Canaveral Space Force Station in Florida ...

simpler designs of rockets than complex, efficient designs (hence the term "big dumb rocket"). Sea Dragon was one of the proposals, led by American rocket engineer Robert Truax, which captured ...