This implies that measurements made in time and space are not absolute, but relative to your particular point of view or reference frame. General relativity bore concepts and theories such as black hole , parallel universes, worm holes, and space-time. About 250 globular clusters form a spherical halo around our galaxy. M13, a bright globular cluster in Hercules, is a classic example easily seen with binoculars or a small telescope. The most feeble of the four fundamental forces in the universe that affect all matter.
Gravity is an attractive force.
The magnitude of gravitational attraction depends directly on mass and inversely on distance squared. The distance separating you from the Sun weakens the mutual gravitational attraction so that the Earth's gravitational pull on you at Earth's surface is 1653 times greater than the Sun's. Ripples in space-time created by the stretching and squeexing effects of massive objects, notably supernovae , orbiting black holes , and orbiting neutron stars . Gravity waves are transverse waves they stretch and squeeze space-time in directions perpendicular to the wave's motion. Einstein's theory of general relativity forecasts their existence, but they have not yet been detected.