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solar system

Our cosmic neighbourhood, consisting of a star – the sun -, eight planets orbiting the sun, numerous smaller bodies, dust and gas.

In the context of relativity, the solar system is interesting as a natural laboratory in which the prediction of general relativity can be tested – in particular those that differ from the predictions of classical, Newtonian gravity. Examples are the relativistic perihelion shift of planetary orbits, the deflection of light close to the sun and the Shapiro effect.

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sun

The central (and most massive) body of our solar system; the star closest to us; a ball of gas with a radius of ca. 700000 km (for comparison the radius of the earth: 12756 km) and a mass of 1.989·10³⁰ kilograms [see exponential notation]. In the interior of the sun, nuclear fusion processes run their course; they are responsible for the sun's impressive brightness.

solar system

Our cosmic neighbourhood, consisting of a star - the sun -, eight planets orbiting the sun, numerous smaller bodies, dust and gas. In the context of relativity, the solar system is interesting as a natural laboratory in which the prediction of general relativity can be tested - in particular those that differ from the predictions of classical, Newtonian gravity. Examples are the relativistic perihelion shift of planetary orbits, the deflection of light close to the sun and the Shapiro effect.

gas

In a strict sense: A state of matter in which the atoms and/or molecules wildly careen and collide, without being bound to each other. This movement leads to an inner pressure, while the average kinetic energy of the moving particles is a measure for the temperature of the gas. Compare the other states of matter: solid state, liquid, plasma. In a broader sense, gas is also used to denote other mixtures of freely careening particles, for instance in the case of the electron gas whose pressure stabilizes a white dwarf against further collapse.

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solar system

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