Fallturm Bremen
Encyclopedia
Center of Applied Space Technology and Microgravity
The Center of Applied Space Technology and Microgravity is a German scientific institution of University of Bremen involved in research in space technology with applications, among other things, in fundamental physics and gravitation....
at the University of Bremen
University of Bremen
The University of Bremen is a university of approximately 23,500 people from 126 countries that are studying, teaching, researching, and working in Bremen, Germany...
in Bremen. It has a 123-metre-high drop tube (actual drop distance is 110 m), in which for 4.74 seconds (with release of the drop capsule), or for over 9 seconds (with the use of a catapult
Catapult
A catapult is a device used to throw or hurl a projectile a great distance without the aid of explosive devices—particularly various types of ancient and medieval siege engines. Although the catapult has been used since ancient times, it has proven to be one of the most effective mechanisms during...
, installed in 2004) weightlessness
Weightlessness
Weightlessness is the condition that exists for an object or person when they experience little or no acceleration except the acceleration that defines their inertial trajectory, or the trajectory of pure free-fall...
can be produced. The entire tower, formed out of a reinforced concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
shank, is 146 metres high.
The 123-metre drop tube is free-standing within the concrete shell, in order to prevent the transmission of wind-induced vibration
Oscillation
Oscillation is the repetitive variation, typically in time, of some measure about a central value or between two or more different states. Familiar examples include a swinging pendulum and AC power. The term vibration is sometimes used more narrowly to mean a mechanical oscillation but sometimes...
s, which could otherwise result in the airtight drop capsule hitting the walls. The drop tube is pumped down prior to every free-fall experiment to about 10 Pa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
(~ 1/10 000 atmosphere). Evacuation takes about 1.5 hours.