In a first, the Jeff Bezos-led spaceflight company simulated lunar gravity on a suborbital rocket to test various science ...
the limiting factor would have become how long the crew could realistically remain cooped up in the tiny Lunar Excursion Module (LEM). In comparison, the Artemis program is far more ambitious.
The module's descent stage - lower part with a big rocket engine - took Apollo ... when they flew into space with astronauts inside. The second lunar module that Grumman ever built, called LM ...