Space

Space is the boundlessthree-dimensional extent in which objects and events have relative position and direction. From the perspective of an Earthling, outer space is a zone that occurs about 100 kilometers (60 miles) above the planet. There is no air. Further, space is a vacuum, meaning that sound cannot carry because molecules are not close enough together to transmit sound between them. Space is not empty. There are planets, stars, galaxies, black holes, in space. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum known as spacetime.