Spin a coin!

How does the exhibit work?

Take a coin from your wallet. Let the coin spin in the blue tub. The closer the coin gets to the hole, the faster it will spin. You don't get the coin back.

What is the science behind it?

The closer your penny gets to the hole, the faster it will spin. All the energy that was needed before to make your penny turn in a big circle is now put into a small circle. So, with the same amount of energy, the penny spins much faster.

The circles your penny makes are similar to the orbit of a satellite around the earth. The closer the satellites are to the earth, the faster they revolve around it.

Your penny eventually disappears into the hole due to gravity. Fortunately, satellites do not fall out of the sky but continue to orbit the earth. All thanks to their great speed!

Satellites for GPS

Thanks to satellites, we know exactly where we are and how to reach our destination.

Satellites for the weather

Satellites observe the earth's weather and climate.

Satellites for high-speed internet

SpaceX, Elon Musk's company, sent many satellites into space in recent years. Each time they are launched, they appear as a line of lights. SpaceX wants to provide the whole world with high-speed internet. A nice goal, but astronomers are worried. The satellites could interfere with their observations.