Clusters Nebulae Galaxies

The Large Magellanic Cloud (LMC), which is visible to the unaided human eye, is a familiar sight to observers in Earth’s southern hemisphere. It looks like a detached piece of the Milky Way.

If you could view it with your eye alone – in the sky visible from Earth’s southern hemisphere – you would say it does resemble a luminous cloud. Really, though, it is a nearby dwarf galaxy, orbiting our Milky Way.

Many people are familiar with the constellation Orion the Hunter. On some moonless winter night, look for the Orion Nebula (M42) a short distance below Orion’s Belt. The unaided eye sees the Orion Nebula as a tiny, hazy spot, but it’s actually a vast area of star formation.

The Butterfly Cluster (M6) and Ptolemy’s Cluster (M7) may well be summertime’s finest star clusters. They can be seen with the unaided eye on a dark, moonless night.

Even with the best of viewing conditions, the M5 globular star cluster is barely detectable to the unaided eye as a faint star. In binoculars, it still appears as a fuzzy star. Turn a small telescope in its direction to see it at its best.

The Wild Duck Cluster (Messier 11) is found in the constellation Scutum the Shield, just south of the Eagle’s Tail in the constellation Aquila. Unless you have eagle eyes, don’t expect to see this distant star cluster with the eye alone. Starting from the star Altair, star-hop to M11′s general location. Then find it with binoculars!

Omega Centauri is the largest and brightest star cluster visible from Earth. It’s in the southern sky and climbs into our northern hemisphere skies on spring evenings.

The Trifid Nebula (Messier 20) is one of the many binocular treasures in the summer Milky Way. Its name means “divided into three lobes,” but you’ll probably need a telescope to see why. On a dark, moonless night, you can star-hop upward from the spout of the Teapot in Sagittarius to the Lagoon Nebula (Messier 8). In the same binocular field, look for the smaller and fainter Trifid Nebula as a fuzzy patch above the Lagoon.

The Coma Cluster is a group of galaxies in the faint constellation Coma Berenices, visible in medium to large amateur telescopes. Coma Berenices lies between Leo and Bootes, and as such is most conveniently viewed in the evening sky of spring and summer. The Coma Cluster is one of the richest galaxy clusters known. How many suns and how many worlds might be located in this direction of space?