We want to investigate what the condensation trails from airplanes,
have to do with elementary particles.
On clear, beautiful days, one can see this phenomenon in the sky. 
When we look at the condensation trails (=contrails), 
we can deduce the direction of flight, the speed,
and the engines. 
We can use the same concept to make elementary particles visible.
An apparatus, which uses the same concepts to make particles visible
is a cloud chamber
Charles Wilson received the Nobel prize for its development
In the II. Institute of Physics in the University of Göttingen,
one can see such a cloud chamber.
If you watch through the glass plate,
you can see a spectacle of almost hypnotic effect.
Contrails appear suddenly, of various forms and sizes 
and disappear shortly afterwards.
Why do we see these contrails?
To answer this question, 
we spoke to a representative of the company that produces this cloud chamber.
The chamber behaves like an airplane travelling in a fog,
the contrails show the path the airplane travel
which we see in the vapour of the chamber.
This behaves in itself, like a particle detector.
The cloud chamber consists of a cooling machine located below
and on top, heating wires to create the cloud.
The vapourised alcohol (pharmaceutical APO)
is heated by the heating wires, and is moved down to the cooler
and when cooled, this vapour becomes 
super saturated.
When a particle passes through this supersaturated vapour,
we see a track being formed
just like that from an airplane passing through the sky.
But what particles can we actually see in the cloud chamber?
To answer that, we ask Priv. Doz. Dr. Jörn Große-Knetter, 
of the University of Göttingen.
There are different types of fundamental particles around us. Some originate from natural radioactivitiy.
we call them alpha, beta, and gamma particles.
On the other hand, there are the so called ‘cosmic rays’ 
which originate from sources in the Universe.
When they travel to Earth, 
they interact with the atmosphere, creating particles
which we can detect on the ground.
Both types of particles are ionizing particles, 
which is how we can detect them. 
We have now seen how we can make invisible particles of the micro cosmos visible through the use of a cloud chamber
This shows the microcosm in action.
With this apparatus, we can study
what glues the universe together, in the microscopic scale.
