Galaxies are big collections of millions or trillions of stars control along by gravity. Our own native galaxy is that the Milky Way. it had been Edwin Powell Hubble United Nations agency given that alternative galaxies existed on the far side the Milky Way. quite half all the galaxies are elliptical (round or oval) in form. the opposite common shapes are spiral galaxies like our Milky Way, barred spirals and irregular galaxies. Besides the Milky Way, 3 alternative galaxies are visible to the optic from the world. they're little and enormous Magellanic Clouds and also the spiral nebula. the little extragalactic nebula could also be the debris of mighty collisions between galaxies. they're little irregular galaxies that orbit the Milky Way once each one.5 billion years. The Andromeda galaxies is nearest to ours. it's concerning 2-3 million light years away and is that the farthest object visible to the human eye.