text: Shortly after sunset and before sunrise, artificial satellites often look like stars – similar in brightness and size – but move relatively quickly. Those that fly in low Earth orbit cross the sky in a couple of minutes. Some satellites, including space debris, appear to blink or have a periodic fluctuation in brightness because they are rotating. Satellite flares can appear brighter than Venus, with notable examples including the International Space Station (ISS) and Iridium Satellites.
  Meteors streak across the sky infrequently. During a meteor shower, they may average one a minute at irregular intervals, but otherwise their appearance is a random surprise. The occasional meteor will make a bright, fleeting streak across the sky, and they can be very bright in comparison to the night sky.
  Aircraft are also visible at night, distinguishable at a distance from other objects because their navigation lights blink.
  Sky map
  Future and past
  Beside the Solar System objects changing in the course of them
  and Earth orbiting and changing orbits over time around the Sun and in the case of the Moon around Earth, appearing over time smaller by expanding its orbit, the night sky also changes over the course of the years with stars having a proper motion and changing brightness because of being variable stars, by the distance to them getting larger or other celestial events like supernovas.
  Over a timescale of tens of billions of years the night sky in the Local Group will significantly change when the coalescence of the Andromeda Galaxy and the Milky Way merge into a single elliptical galaxy.