The bold question-askers at What If present a radical new plan for space travel using hydrogen balloons instead of rockets.

Artemis rocket launch delayed for 2nd time in a week 01:36. NASA's star-crossed Space Launch System moon rocket was grounded for the second time in five days Saturday, this time by a large ...

A hydrogen leak prevented the launch of NASA’s SLS rocket this Saturday, in what is a troubling yet highly predictable development.

Born into this world as America's first liquid hydrogen rocket engine, it was continuously improved, and it will continue to be so for many years to come. The newest iteration of the powerplant? A ...

Some rocket launches have experimented with gases such as argon and nitrogen, which are also inert and can sometimes be cheaper. Helium, however, is much more prevalent in the industry.

Helium is inert - it does not react with other substances or combust - and its atomic number is 2, making it the second lightest element after hydrogen. Rockets need to achieve specific speeds and ...