Solar System Objects
When one observes the sun using a proper filter—and this is an absolute must, since one will severely and permanently injure one's eye without proper solar filtering—the sun offers a constantly evolving view of sunspots and other subtle detail.
Go to my solar astronomy page for more thoughts on this fascinating niche within the hobby.
The easiest thing to find in the night sky, the moon offers lots of detail in the eyepiece of a telescope. Each phase of the moon reveals different parts of its character.
Saturn is one of my very favorite objects to observe. I'm always amazed to see Cassini's Division and more subtle cloud belts on the planet's disk. Indeed, to be able to see that much detail on something 746 million miles away with only a modestly sized telescope in my backyard is truly astounding.
Another source of fascination for me is the King of the Planets. Along with the four Galilean moons—Io, Europa, Ganymede, and Callisto—one can also see the Great Red Spot and variously colored cloud belts on the surface of Jupiter.
Because of a runaway greenhouse effect in an atmosphere made up mostly of carbon dioxide, Venus is the hottest planet in our solar system even in spite of the fact that it is further from the sun than Mercury. Like the moon, it has phases as it orbits the sun, and it's visible to us either before sunrise or after sunset.
Deep Space Objects
Messier 31 / Andromeda Galaxy
Galaxy in Andromeda (0h 42m +41°)
M31 shows an intense oval core with a hazy streak running through the core and crossing almost the entire field of view. Satellite galaxy M32 appears as a small, somewhat dim, but noticeable haze on one side. Another satellite galaxy, M110, shows up as larger but very vague haze further away.
NGC 457 / Owl Cluster
Open Star Cluster in Cassiopeia (1h 19m +58°)
A very interesting cluster that fills the whole field of view of a low-power eyepiece, the shape of an owl with its wings spread is immediately apparent, as are two conspicuous "eyes" at its head.
NGC 869 and 884 / Double Cluster
Open Star Cluster in Perseus (2h 19m +57°)
A rich pair of clusters between which I will often move my scope back and forth to observe (fitting them both in the same field of view in my lowest powered eyepiece is a challenge). Each cluster has around 20 or 30 brighter members which are fairly densely compressed. NGC 869 has a number of reddish stars and is definitely tighter than its looser neighbor. NGC 884 has a conspicuous orange star near its middle. The pair appear very nice even in a small scope.
Messier 45 / The Pleiades
Open Star Cluster in Taurus (3h 47m +24°)
Visible in the naked eye as a haze even in urban light pollution, the Pleiades, for the ancients, was a test of one's eyesight. In binoculars, this cluster appears as a wonderful gathering of several very bright stars. In a telescope at lower power, around 60 stars ranging from dim and fine to brilliantly bright all coarsely clustered across the entire field of view with the seven brightest stars forming a dipper asterism.
Messier 42 / Great Orion Nebula
Reflection and Emission Nebula in Orion (5h 35m -05°)
The superstar of the winter sky, the Great Orion Nebula is situated just below Orion's belt and is visible to the naked eye even in the city. Through the eyepiece of a telescope, I've spent lots of time gazing at its intricate and sprawling detail.
Open Star Cluster in Auriga (5h 52m +32°)
In a telescope with modest magnification, M37 is a swarm of countless pinpricks of light surrounding a conspicuous red giant near the center of this open cluster. This star cluster is lovely even in a small scope.
Open Star Cluster in Gemini (6h 08m +24°)
Filling the whole field of view of a low-power eyepiece is this amazing mass of colorful stars. Some 100 to 120 mostly white, bright stars richly clustered into a rough triangle shape with a few orange stars here and there, the cluster covering much of the field of view. Beautiful!
Messier 81 and 82
Galaxies in Ursa Major (9h 55m +69°)
M81 appears as a broad oval glow with a roundish, compact, and fairly intense core—like a mini Andromeda Galaxy. M82 appears as a long, narrow, uniformly bright streak with subtly mottled texture that is interesting to observe.
Zeta Ursae Majoris / Mizar and Alcor
Double Star in Ursa Major (13h 23m +54°)
One of the stars in the Big Dipper's handle is actually two stars, Mizar and Alcor, which are easily seen in binoculars. In a telescope, Mizar, the brighter of the two, is itself a double.
Globular Star Cluster in Canes Venatici (13h 42m +28°)
A relatively compact glob whose core fades gradually and evenly towards the periphery with a fine spread of stars that are evenly distributed. Very nice.
Globular Star Cluster in Serpens Caput (15h 18m +2°)
This glob's brightest stars resolved in direct vision and its powdery glittering appearance popped into resolution in averted vision, all accompanied by a bright core fading gradually towards the periphery. Beautiful even in a small scope.
Globular Star Cluster in Hercules (16h 41m +36°)
Perhaps the most famous globular cluster in the northern hemisphere, M13 is often the first object to which I'll turn my telescope once the sky darkens at night in the summer. It's a wonderful aggregation of finely resolving stars spread across a wide area. A broad spray of mostly equally bright and equally distributed stars that resolve in direct vision and that are arranged in twisting rows that radiate towards the outside of the cluster, the center of the glob missing a well-defined core.
Globular Star Cluster in Hercules (17h 17m +43°)
While I often find myself going for M13 mainly because it's so easy to find in the keystone shape of Hercules, M92 is sometimes more satisfying to observe. It has an intensely glowing core surrounded by a spray of stars.
Epsilon Lyrae / Double Double
Double Star in Lyra (18h 44m +39°)
In a pair of binoculars, Epsilon Lyrae appears as two stars relatively close to each other. Turning to a telescope with higher magnification, one will realize that each star is in fact two doubles themselves, each a very tight pair that can be somewhat of a challenge to split.
Messier 8 / Lagoon Nebula
Emission Nebula in Sagittarius (18h 03m -24°)
With UHC filter, some 25 bright, moderately compressed stars off to one side, two bright stars on the other side both surrounded by a bright region of nebulosity, and a well-defined U-shaped dark lane that divided the nebulosity into regions.
Messier 17 / Swan Nebula
Emission Nebula in Sagittarius (18h 20m -16°)
A long, relatively thick, bright, and well-defined streak that has a fainter hook-shaped extension that makes up the "neck" of the "swan," that neck not as well defined as the body but still visible in direct and especially in averted vision.
Messier 11 / Wild Duck Cluster
Open Star Cluster in Scutum (18h 51m -06°)
In my eight-inch Schmidt-Cassegrain telescope at 100x, I would estimate that some 100 or 150 stars are densely packed together in this wonderful open cluster. It gets its name the Wild Duck Cluster from its "V"-shaped resemblance to a flock of flying ducks. It's my very favorite open star cluster, worth every minute of the many times I've spent observing it.
Messier 57 / Ring Nebula
Planetary Nebula in Lyra (18h 53m +33°)
A tiny donut-shaped puff of nebulosity, the Ring Nebula is easy to find between two bright stars near Vega. More aperture will reveal subtle detail, but most telescopes will be able to pick up its distinctive ring.
Collinder 399 / Brocchi's Cluster / The Coat Hanger
Asterism in Vulpecula (19h 25m +20°)
With its line of stars with a hook-shaped string in the middle, this fun-to-observe wide pattern of stars resembles, as its name suggests, a coat hanger. It's best seen through a pair of binoculars. I took the above image through a telescope using very low power.
Beta Cygni / Albireo
Double Star in Cygnus (19h 30m +43°)
Albireo is one of the most beautiful double stars in the sky. A golden yellow primary and sapphire blue secondary make for a very interesting pair to observe.
Messier 27 / Dumbbell Nebula
Planetary Nebula in Vulpecula (19h 59m +22°)
An hourglass- or eaten apple core-shaped mass that appears bright against a relatively dense star field, the nebula in averted vision showing subtle hints of hazy extensions perpendicular to the length of the hourglass shape.
Globular Star Cluster in Pegasus (21h 30m +12°)
A glittering sugary heap of stars that resolve well and that extend out widely from an intense, compact core, the glob taking increased magnification well up to 226x.
Globular Star Cluster in Aquarius (21h 33m +0°)
A broad, moderately bright, and uniform core surrounded by a halo of stars that does not extend too far from the core, the glob resolving especially in averted vision. Far more subtle than nearby M15.