One of our most famous spiral galaxies, the Whirlpool Galaxy (NGC 5194) interacts with a companion galaxy (NGC 5195) and is easily observed even in binoculars. Recent simulations have demonstrated that M51's spiral structure was caused by NGC 5195 passing through M51´s main disc 500 to 600 million years ago. The model supposes that NGC 5195 came from behind NGC 5194 through the disk and crossed back 50 to 100 million years ago, until it is where we observe it today behind NGC 5194.

The two galaxies are sometimes referred to as M51a and M51b. M51 is estimated to contain several hundred billion stars.

The Whirlpool Galaxy is a popular target for professional astronomers, as a study into galaxy structures and interactions.

M52 is an open cluster in the Milky Way which can be seen in good binoculars or finder scopes as a nebulous patch and further resolved in telescopes. In 4-inch telescopes, it appears as a fine compressed cluster of faint stars, often described as fan or V shaped.

M52 is thought to contain about 200 stars up to the relatively young age of 35 million years.

At about 60,000 light years from the Galactic centre, M53 is one of the more outlying globular clusters. It is nearly the same distance, about 56,000 light years, from the Solar System.

In small telescopes, M53 appears as a slightly oval nebulous object with a large, bright centre, and even surface brightness fading out to the edges. In a 4-inch refractor under excellent viewing conditions, the central part appears grainy. In larger telescopes of about 8-inch aperature, the outer fringes are resolved into stars, while the central part is still unresolved and grainy, with a lone star standing out. Larger instruments of about 12-inches upwards show M53 well resolved, with a moderately concenterated nucleus and stars spread out to about 12 arc minutes diameter.

In 1994 it was discovered that the globular cluster M54 is not, as was previously believed, a member of the Milky Way but is more distant and belongs to a newly discovered Dwarf Elliptical Galaxy know a SagDEG (Sagittarius Dwarf Elliptical Galaxy).

The M54 cluster is bright but small so may be overlooked or mistaken for a star in smaller binoculars or finder scopes. Because of its great distance M54 is difficult to resolve and binoculars or small telescopes show it as a round nebulous object gradually fading toward the edges. A 4-inch telescope will show a mottled texture under good conditions and even in larger amateur telescopes M54 appears more like a planetary nebula at first sight.

M55 is a large globular cluster, appearing roughly as two thirds of the Moon´s apparent diameter, with a loose appearence. In 7x50 binoculars, M55 can appear very grainy, further resolved in larger telescopes.