How do we use a telescope to study the universe?
A telescope does gather light and magnify it so we can see what we could not with the naked eye. Also, a telescope is in a sense a “Time Machine”. The more distant the object, the further back in time you will be seeing it. Light is an electromagnetic wave which takes time to travel through space. The light that you see from the sun is actually the light that was emitted from it around 11 minutes before hand. A light-year is the distance that light travels in a year. If a galaxy or anything very distant is being viewed (lets say 100 million light-years away), you would be seeing that object as it was 100 million years ago. Telescopes help us study the universe by looking into the past of the universe, but there is a limit. Some of the furthest away and earliest galaxies can be seen in the Hubble deep field (look it up). What the photo shows are many galaxies very close together that probably don’t even exist any more.
