Related topics: galaxies · physical review letters · dark matter · moon · nasa

Monitoring groundwater changes more precisely

A new method could help to track groundwater changes better than before. To this end, researchers from Potsdam and Oberlin, Ohio (USA), have compared gravity field data from the GRACE and GRACE-Follow On satellite missions ...

Black holes? They are like a hologram

According to new research by SISSA, ICTP and INFN, black holes could be like holograms, in which all the information to produce a three-dimensional image is encoded in a two-dimensional surface. As affirmed by quantum theories, ...

Levitated timepiece sets new benchmark

A new mechanical "clock" has been created by an international team of researchers, led by scientists at the University of St Andrews, which could test the fundamental physics of gravity.

Making cells ultra-heavy

The life of a fibroblast is heavy, but PhD student Julia Eckert makes it 19.5 times heavier, using the Large Diameter Centrifuge at the ESTEC space research centre in Noordwijk.

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Gravitation is a natural phenomenon by which objects with mass attract one another. In everyday life, gravitation is most commonly thought of as the agency which lends weight to objects with mass. Gravitation compels dispersed matter to coalesce, thus accounting for the existence of the Earth, the Sun, and most of the macroscopic objects in the universe. It is responsible for keeping the Earth and the other planets in their orbits around the Sun; for keeping the Moon in its orbit around the Earth; for the formation of tides; for convection, by which fluid flow occurs under the influence of a temperature gradient and gravity; for heating the interiors of forming stars and planets to very high temperatures; and for various other phenomena observed on Earth. Modern physics describes gravitation using the general theory of relativity, in which gravitation is a consequence of the curvature of spacetime which governs the motion of inertial objects. The simpler Newton's law of universal gravitation provides an accurate approximation for most calculations.

The terms gravitation and gravity are mostly interchangeable in everyday use, but a distinction is made in scientific circles. "Gravitation" is a general term describing the phenomenon by which bodies with mass are attracted to one another, while "gravity" refers specifically to the net force exerted by the Earth on objects in its vicinity as well as by other factors, such as the Earth's rotation.

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