Also known as 47 Tucanae, this object in the skies of the southern hemisphere is the second largest and brightest globular cluster of stars. It is nearly 17,000 light years distant and contains millions of stars of many interesting types. The Hubble space telescope was used to study the cluster in 2000 by watching 35,000 stars for 8 days expecting to find some extra-solar planets. It found none. The image below is of one quadrant of the cluster.
There are two kinds of star clusters. There are open clusters and globular clusters. Open clusters are loose groupings that have fewer stars and can be seen through. Globulars are so dense with stars you cannot see through their center.
Sculptor Galaxy, aka Silver Coin, or Silver Dollar Galaxy, is in a period of intense star formation. It was discovered by Caroline Herschel in 1783. Sculptor is one of the brightest galaxies in the skies of the northern hemisphere. Research suggests there is a 5 million solar mass black hole at the center which is more massive than the one in our Milky Way galaxy center.
This spiral galaxy is a fine example in the constellation Pisces of the northern hemisphere. It is about 32 million light-years from Earth. It is not bright and is difficult for amateur astronomers to observe. It is estimated to be made up of about 100 billion stars. Darker lanes of dust are visible throughout. The crossed lines are imaging artifacts.
This emission nebula region is inside the Triangulum Galaxy in the skies of the northern hemisphere. The nebula was discovered by William Herschel on September 11, 1784. It is an estimated distance of 2.7 million light-years from Earth. If this object was the same distance as the Orion Nebula, it would outshine Venus. The glowing clouds of gas are ionized by a cluster of about 200 massive stars at the center.