Saint Veronica With The Veil (Original Piece By Mattia Preti C.1655-1660) Touched By Clayshaper

How many people can say they have played rugby with a Beluga whale? 🐳 🏉

Allegory of the Cave

Albert Einstein, Physics and Reality [General Consideration Concerning the Method of Science] (1939), in Out of My Later Years, Philosophical Library, New York, NY, 1950, pp. 59-65

A delightfully concise animated proof of the sum of the arithmetic progression of the naturals.

Mathematics is beautiful. <3

Pan (moon of Saturn) - March 07 2017

NASA/JPL-Caltech/SSI/Kevin M. Gill

Kumamoto,Japan | takaphilography

Orbit change of artificial satellite

In order to raise the altitude of an artificial satellite, it is necessary to accelerate it. When the orbital speed increases, the centrifugal force generated by the rotation of the satellite becomes stronger than the gravity of the earth applied to it, then the altitude rises. At this time, a certain amount of energy is returned from the satellite to the vacuum space to reduce the energy debt. Hence the orbital speed decreases and finally drops below the initial speed. The sum of the reduced amount of the momentum energy and the energy required for the acceleration is returned to the vacuum space.

In order to lower the altitude of an artificial satellite, it is necessary to decelerate it. When the orbital speed decreases, the centrifugal force becomes weaker than the gravity, then the altitude drops. At this time, the satellite is given a certain amount of energy from the vacuum space. Hence the orbital speed increases and finally rises above the initial speed. The sum of the increased amount of the momentum energy and the energy released by the deceleration is borrowed from the vacuum space.