Satellite prototype used to confirm the design and performance of the final flight model.
Theory of physics that explains the behaviour of nature and its forces on a very small, subatomic scale. It states that physical quantities can only have discrete values (this is quantization). According to quantum mechanics photons or electrons may be considered as particles but they can also be diffracted like waves (this is referred to as wave-particle duality). This quantum theory was proposed by Max Planck in 1900. Quantum mechanics is the more formal mathematical description of his theory which was developed in the 1920's. It also incorporates the uncertainty principle, which states that you cannot measure a particle's position and velocity at the same time. The more accurately you know its position, the less accurately you know its velocity and vice versa.
An elementary particle which is believed to be the fundamental structural unit from which all other particles are made. There are six quarks: up, down, strange, charm, top and bottom. A proton is made up of one down quark and two up quarks.
Quasi-stellar extragalactic object.
Initial examination of scientific data before further processing and investigation.