It’s almost impossible to replicate the effects of zero gravity here on Earth, and that’s one of the reasons why scientists are willing to spend so much of their funding to send experiments to the International Space Station. Albeit not a perfect replication of the microgravitational environment in outer space, it’s possible to simulate near-zero gravity with something called a drop tower. That’s one reason why Germany is such a popular place to send gravity-centric experiments, as it’s home to one of the world’s most advanced drop towers.
The Bremen Drop Tower is approximately 140 meters tall and comprises of a vertical vacuum chamber that measures 120 meters in height. Experiments can be dropped from the top of the drop shaft, allowing scientists to see what happens in near-perfect weightlessness for a short time. Before it reaches the bottom, a deceleration chamber slows the payload down before it can come crashing back down to ground level.
Why is zero gravity such a big deal to scientists? A good question, and obviously worthy of a valid answer. The primary reason is that chemistry and physics behave differently in zero-gravity environments. In this environment, scientists are able to study behaviorisms that can’t be replicated under Earth’s gravitational pull, and moreover, different states of matter tend to present themselves.
The Bremen Drop Tower is a cheap alternative to ferrying experiments into space, which makes it easy to repeat experiments time and time again. It takes almost 4.7 seconds for the payload to reach the bottom, and a catapult at the bottom of the drop tower can launch the payload back up a second time to generate up to 10 seconds of simulated weightlessness.
Related: NASA wants to know how fire behaves in microgravity