All those 60s, 70s, 80s and 90s kids out there may remember the classes of model rocket engines – generally A, B, C, and D sized engines used to push your cardboard tube with balsa fins skyward.

It was the first time Bezos' company, Blue Origin, had operated the entire stacked rocket as an integrated system. Flashes from the engines pierced ... transition to a new model of space research ...