Where do these objects come from, and why are there so many types?
Types of Deep Sky Objects
- gas clouds are collapsing, exploding and colliding.
- stars are forming, evolving, and dying.
- all gather into galactic groups due to their mutual gravitational attraction.
- these processes take millions of years or more to happen, so human lifetime is sufficient to observe the evolution of a star.
One place or another
Even our local patch of universe is large enough that we can see all the stages of these processes happening in one place or another – it is similar to walking down the street and seeing adults, children of all sizes, and pregnant women. So soon the picture of how humans are born and grow up becomes apparent – without actually witnessing a person pass through every stage.
Over the past several centuries, astronomers have mad observations of these objects, and have teased out the physical processes involved by scrutinising their light. Using spectroscopy and other techniques; we now have a fairly clear idea of what we are looking at – even of our understanding of their formation is not yet perfect – let’s run through the major types of objects that you can observe with your telescope today.