Velocity Milky Way

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In the general sense, the absolute velocity of any object through space is not a meaningful question according to Einstein's Special Theory of Relativity, which declares that there is no "preferred" inertial frame of reference in space with which to compare the galaxy's motion. (Motion must always be specified with respect to another object.) With this in mind, many astronomers believe the galaxy is moving through space at approximately 600km per second relative to the observed locations of other nearby galaxies. Most recent estimates range from 130 km/s to 1,000 km/s. If indeed the Milky Way is moving at 600 km per second, we are traveling 51.84 million km per day, or more than 18.9 billion km per year. For comparison, this would mean that each year, we are traveling about 4.5 times the distance that Pluto lies from the Earth (at its closest). The Milky Way is thought to be moving in the direction of the constellation Hydra, and may someday become a close-knit member of the Virgo cluster of galaxies. Another reference frame is provided by the Cosmic microwave background (CMB). The Milky Way is moving at around 552 km/s[30] with respect to the photons of the CMB. This can be observed by satellites such as COBE and WMAP as a dipole contribution to the CMB, as photons in equilibrium at the CMB frame get blue-shifted in the direction of the motion and red-shifted in the opposite direction.