Drawings discovered in 1967 showed this artist invented the chain drive around 1492
In 1960 Theodore Maiman used this gem in his laser
Bell invented it in 1876; David Hughes gave it this name in 1878, & don't lean into it when you reply
Christiaan Huygens got into the swing of things in 1656 by adding this to the clock
The first rockets were used in this country as early as 1232
Added thrust for takeoffs is provided by these extra rockets attached to the first stage
After World War II, the U.S. used these captured German rockets as atmospheric probes
One of Goddard's early inventions was developed into this anti-tank rocket gun
They're fired to slow down the movement of a space vehicle
You could also call it Woodchuck Day