It’s calculated that there are over 100 billion galaxies in the observable universe. Tonight (July 8, 2016) the folks at Cline Observatory are scheduled to feature one, The Sombrero Galaxy.
100 billion galaxies in the observable universe! Isn’t that amazing.
First, I’ll try to wrap my head around “observable universe.”
Imagine standing on the top Mt. Mitchell, the tallest mountain in North Carolina. You gaze out at the landscape below you. You cannot see all the surface of the Earth from your vantage point.
As high as you are, you can’t see New York City, or even Charlotte. You can see only the part of the surface of the Earth that is within your range, that’s the observable surface of the Earth to you.
The universe is expanding, and the further away a galaxy is, the faster it’s moving away. Apparently some galaxies are so far away they are receding faster than the speed of light. (They are not MOVING faster than the speed of light, the space between us and them is expanding so much.) So these galaxies would be over our horizon, not part of our observable universe.
How big is the unobservable universe? We don’t know.
But in our area, in our observable universe, there are about 100 billion galaxies. I don’t have very many every-day occasions to use the word billion, so while the word rolls of my tongue, my gut understanding may be lacking. A billion is a huge number.
You know what a second in time is: 60 seconds in a minute, right? Look at your watch and see the seconds tick by, Now…and Now… and Now.
Have you been alive for 100 billion seconds? Not unless you’re older than 3,000 years! One billion seconds is just over 31 years. A billion is a huge number.
One of those 100 billion galaxies we can see in our observable universe is M104, the Sombrero Galaxy. You can find it between the constellations Corvus and Virgo. It’s a nice bright galaxy slightly larger than the Milky Way Galaxy and about 40 million Light Years away.
If you’ve never seen it, tonight may be your lucky night. M104 is the featured object for the public observing session at Cline Observatory.
Cline Observatory, located on the Jamestown campus of Guilford Technical Community College, is open to the public every clear Friday night, free of charge.
From March thru October the regular Friday night public observing sessions begin about 30 minutes after sunset. Sessions usually last about two hours.
The observatory is open to the night air so please dress appropriately.
For more information and directions please see the Observatory website at: