Jam Sandwich (James) asked:
When sending a spacecraft to the moon (230,000 miles away) - at a rough guess at about 8,000 mph, how did the command module reduce its speed in space (no friction) to land in a graceful way on the Moon?
This is all based on rockets and thrusters. The moon landing was done by going into orbit around the moon, and then a small command module detached and went down to land on the surface, using thrusters to control the speed and angle of descent. In the rocket or thruster it pushes gas out of the rocket, so the gas pushes the spaceship in the other direction.
Actually, there was a hair-raising moment during Neil Armstrong’s moon landing. The landing is usually all computer controlled, but he realised that they were going to land in a boulder field, which would basically cause them to crash. He took manual control away from the computer, and landed safely with only 16 seconds of fuel left.