Bode's Galaxy (M81)
This spiral galaxy, M81, is quite a bit smaller than our Milky Way, but it contains about the same amount of stars, 250 million. This gallaxy is 12 million light years from earth.
A fact to remember:
To measure really long distances, astronomers use a unit called a light year. A light year is the distance that light travels in a year. Light travels at 186,000 miles per second so to get a light year we use the following calculation:
186,000 miles/second * 60 seconds/min. * 60 min./hour * 24 hours/day * 365 days/year = 5,865,696,000,000 miles/year
That means a light year is 5.87 trillion miles.
So that puts Bode's Galaxy at 70.44 million trillion miles from earth. That's not just around the corner!
The Lagoon Nebula (M8)
This diffuse nebula, also known as NGC 6523, gets its name from a dark lane that divides it in two. The brightest part of the nebula is called the Hourglass. The Lagoon Nebula is 5000 light years away.
The Great Orion Nebula (M42)
I posted a previous picture of this nebula last year, but I like this picture taken in March 2011 even better. The Orion
Nebula (a.k.a. Messier 42, M42, or NGC 1976) is one of the brightest nebulea and is
visible to the naked eye in the night sky. M42 is located at a distance
of 1,344 light. It is the closest region of massive star formation to Earth.
The M42 nebula is about 24 light years across.
Here are some gobular star clusters. A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite.
Hercules Star Cluster (M13)
The Hercules Star Cluster (M13), also posted in 2010, is just visible to the naked eye and is the best example of a globular cluster visible in the Northern Hemisphere. The entire cluster contains perhaps 100,000 or more stars. In its central portion, the stars are so close together that they cannot be resolved, despite the cluster's relatively near distance of 35,000 light-years.
NCG 6121 Star Cluster (M4)
NCG 6121 Star Cluster (M4) is a somewhat loosely concentrated cluster that measures 75 light years across. It features a characteristic "bar" structure across its core, and is visible to moderate sized telescopes. M4 is about 7,200 light years away, making it one of the closest globular clusters to Earth.
NGC 6341 Star Cluster
NGC 6341 (a.k.a. Messier 92 or M92) contains about 330,000 stars, and
is about 26,700 light years from Earth.