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Celestial sphere

The celestial sphere is the apparent sphere of the sky; a sphere of large radius centered on the observer; directions of objects in the sky


A supersolid is a spatially ordered material with superfluid properties. At very low temperatures, close to absolute zero, matter behaves strangely: fluids flow without friction

Degenerate matter

Degenerate matter is a highly dense state of fermionic matter in which particles must occupy high states of kinetic energy in order to satisfy the


An electrophone is one of the five main classes of electric or electronic musical instruments in the Hornbostel–Sachs classification system. A musical instrument that uses


Ablation is the removal of material from the surface of an object by vaporization, chipping, or other erosive processes. Ablation may refer to the removal

Seebeck effect

The Seebeck effect, discovered by Thomas Johann Seebeck in 1821, is a thermoelectric effect by which, in a circuit made up of two different metal