In mathematics, a 3-sphere is a higher-dimensional analogue of a sphere. It consists of the set of points equidistant from a fixed central point in
In astronomy, Kepler’s laws of planetary motion are three scientific laws describing the motion of planets around the Sun.
1- The orbit of
Specific Orbital Energy
In the gravitational two-body problem, the specific orbital energy (or vis-viva energy) of two orbiting bodies is the constant sum of their mutual
Cycloid (Cartesian equation)
A cycloid is the curve traced by a point on the rim of a circular wheel as the wheel rolls along a straight line without slippage. It is an example of a
Proper motion (declination)
Proper motion is the astronomical measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the
Center of mass (for two particles)
The center of mass of a distribution of mass in space is the unique point where the weighted relative position of the distributed mass sums to zero.