It is difficult to believe that this will be the last space shuttle launch.

Clearly, I must do something to commemorate this event. But what? How about I look at space ships in orbit and consider the energy required. WITH GRAPHS.

First, what orbit am I talking about? Let me assume low Earth orbit — which is about 360 km above the surface of the Earth. Now, you need to realize that in order to be in this orbit, the object has to go at a certain speed. The only force acting on the mass would be the gravitational force. The acceleration that goes along with this force is the acceleration of an object moving in a circle.

Since you have to get this thing going fast, it must increase in kinetic energy. Also, since it has to increase in distance from the center of the Earth, it must increase in gravitational potential energy (technically, the Earth-mass system increase in gravitational potential energy).

I will skip all the intermediate steps and show you the change in energy need to get an object into orbit. Here are all the details if you are interested.