Reference

Deep-sky object database

28 objects with coordinates, angular size and honest difficulty ratings. Sort any column, filter by type, magnitude, season or difficulty, expand a row for observing notes, and compare up to three objects side by side.

Designation	Name	Type	Magnitude	Apparent size	RA	Dec	Season	Difficulty
M42	Orion Nebula	Emission nebula	4.0	85 × 60 arcmin	05h 35m	-05° 23′	Winter	Easy
ConstellationOrion Best seasonWinter from northern latitudes What to expectThe brightest diffuse nebula in the sky; visible to the unaided eye as the middle "star" of Orion's sword.
M31	Andromeda Galaxy	Spiral galaxy	3.4	190 × 60 arcmin	00h 43m	+41° 16′	Autumn	Easy
ConstellationAndromeda Best seasonAutumn from northern latitudes What to expectThe nearest large spiral galaxy and the most distant object visible to the unaided eye.
M45	Pleiades	Open cluster	1.6	110 arcmin	03h 47m	+24° 07′	Winter	Easy
ConstellationTaurus Best seasonWinter from northern latitudes What to expectA young open cluster whose brightest members are wrapped in reflection nebulosity.
M57	Ring Nebula	Planetary nebula	8.8	1.5 × 1 arcmin	18h 53m	+33° 02′	Summer	Moderate
ConstellationLyra Best seasonSummer from northern latitudes What to expectA classic planetary nebula; an OIII filter makes the ring obvious in small apertures.
M51	Whirlpool Galaxy	Spiral galaxy	8.4	11 × 7 arcmin	13h 30m	+47° 11′	Spring	Moderate
ConstellationCanes Venatici Best seasonSpring from northern latitudes What to expectA face-on spiral with a companion; spiral structure needs aperture and a dark sky.
M13	Hercules Cluster	Globular cluster	5.8	20 arcmin	16h 42m	+36° 28′	Summer	Easy
ConstellationHercules Best seasonSummer from northern latitudes What to expectThe finest globular cluster in the northern sky; resolves into stars from about 150 mm up.
M27	Dumbbell Nebula	Planetary nebula	7.4	8 × 5.7 arcmin	19h 59m	+22° 43′	Summer	Moderate
ConstellationVulpecula Best seasonSummer from northern latitudes What to expectA large, bright planetary nebula that responds strongly to an OIII filter.
M8	Lagoon Nebula	Emission nebula	6.0	90 × 40 arcmin	18h 04m	-24° 23′	Summer	Easy
ConstellationSagittarius Best seasonSummer from northern latitudes What to expectA large emission nebula with a bright open cluster embedded in its core.
M33	Triangulum Galaxy	Spiral galaxy	5.7	73 × 45 arcmin	01h 34m	+30° 39′	Autumn	Hard
ConstellationTriangulum Best seasonAutumn from northern latitudes What to expectLarge and faint — its low surface brightness makes it a classic dark-sky test object.
M81	Bode's Galaxy	Spiral galaxy	6.9	26 × 14 arcmin	09h 56m	+69° 04′	Spring	Moderate
ConstellationUrsa Major Best seasonSpring from northern latitudes What to expectA bright spiral paired with M82 in the same medium-power field.
M82	Cigar Galaxy	Starburst galaxy	8.4	11 × 4 arcmin	09h 56m	+69° 41′	Spring	Moderate
ConstellationUrsa Major Best seasonSpring from northern latitudes What to expectAn edge-on starburst galaxy with visible dust lanes in modest apertures.
M104	Sombrero Galaxy	Spiral galaxy	8.0	8.7 × 3.5 arcmin	12h 40m	-11° 37′	Spring	Moderate
ConstellationVirgo Best seasonSpring from northern latitudes What to expectA bright bulge crossed by a sharp dust lane; unmistakable once found.
M1	Crab Nebula	Supernova remnant	8.4	7 × 5 arcmin	05h 35m	+22° 01′	Winter	Hard
ConstellationTaurus Best seasonWinter from northern latitudes What to expectThe expanding remnant of a supernova recorded in 1054 CE.
M44	Beehive Cluster	Open cluster	3.7	95 arcmin	08h 40m	+19° 41′	Winter	Easy
ConstellationCancer Best seasonWinter from northern latitudes What to expectA large, sparse open cluster best seen in binoculars or a wide-field eyepiece.
M22	Great Globular Cluster	Globular cluster	5.1	32 arcmin	18h 36m	-23° 54′	Summer	Easy
ConstellationSagittarius Best seasonSummer from northern latitudes What to expectOne of the brightest globulars; low declination makes it hard work from northern latitudes.
NGC 7000	North America Nebula	Emission nebula	4.0	120 × 100 arcmin	20h 59m	+44° 31′	Summer	Moderate
ConstellationCygnus Best seasonSummer from northern latitudes What to expectHuge and diffuse; a UHC or H-beta filter and a wide field make the shape readable.
NGC 6960	Veil Nebula	Supernova remnant	7.0	70 × 6 arcmin	20h 46m	+30° 43′	Summer	Hard
ConstellationCygnus Best seasonSummer from northern latitudes What to expectA filamentary supernova remnant; an OIII filter is effectively required.
NGC 869/884	Double Cluster	Open cluster	4.3	60 arcmin	02h 20m	+57° 08′	Autumn	Easy
ConstellationPerseus Best seasonAutumn from northern latitudes What to expectTwo young open clusters side by side — one of the best low-power sights in the sky.
M97	Owl Cluster	Planetary nebula	9.9	3.4 arcmin	11h 15m	+55° 01′	Spring	Hard
ConstellationUrsa Major Best seasonSpring from northern latitudes What to expectA dim, round planetary nebula; the two dark "eyes" need a large aperture.
M11	Wild Duck Cluster	Open cluster	6.3	14 arcmin	18h 51m	-06° 16′	Summer	Easy
ConstellationScutum Best seasonSummer from northern latitudes What to expectOne of the richest open clusters, with hundreds of members in a compact field.
M16	Eagle Nebula	Emission nebula	6.0	35 × 28 arcmin	18h 19m	-13° 49′	Summer	Moderate
ConstellationSerpens Best seasonSummer from northern latitudes What to expectHome of the Pillars of Creation; the associated open cluster is the easy part.
NGC 5139	Omega Centauri	Globular cluster	3.9	36 arcmin	13h 27m	-47° 29′	Spring	Easy
ConstellationCentaurus Best seasonSpring from northern latitudes What to expectThe largest globular cluster orbiting the Milky Way — visible to the unaided eye from dark southern skies.
NGC 2070	Tarantula Nebula	Emission nebula	8.0	40 × 25 arcmin	05h 39m	-69° 06′	Winter	Easy
ConstellationDorado Best seasonWinter from northern latitudes What to expectA vast star-forming region in the Large Magellanic Cloud, visible from southern latitudes.
ESO 350-40	Cartwheel Galaxy	Lenticular galaxy	12.5	1.1 arcmin	00h 37m	-33° 43′	Autumn	Hard
ConstellationSculptor Best seasonAutumn from northern latitudes What to expectA ring galaxy formed by a collision; a genuine challenge object for large apertures.
Barnard 33	Horsehead Nebula	Dark nebula	6.8	8 × 6 arcmin	05h 41m	-02° 27′	Winter	Hard
ConstellationOrion Best seasonWinter from northern latitudes What to expectA dark dust column silhouetted against IC 434; an H-beta filter helps considerably.
M101	Pinwheel Galaxy	Spiral galaxy	7.9	28 × 26 arcmin	14h 03m	+54° 21′	Spring	Moderate
ConstellationUrsa Major Best seasonSpring from northern latitudes What to expectA large face-on spiral; low surface brightness makes it a dark-sky object.
NGC 6543	Cat's Eye Nebula	Planetary nebula	8.1	1.2 arcmin	17h 59m	+66° 08′	Summer	Moderate
ConstellationDraco Best seasonSummer from northern latitudes What to expectA small, bright, structurally complex planetary nebula that takes high magnification well.
Collinder 399	Coathanger Cluster	Asterism	3.6	60 arcmin	19h 25m	+20° 11′	Summer	Easy
ConstellationVulpecula Best seasonSummer from northern latitudes What to expectA coathanger-shaped asterism best appreciated in binoculars or a very wide field.

Click any row for observing notes. Coordinates are J2000 and rounded; difficulty ratings assume a 150 mm telescope under reasonably dark skies and will differ with your aperture and your sky.

Side-by-side comparison

Magnitude is integrated brightness, not surface brightness. A large, faint object like M33 can be harder than its magnitude suggests, while a small bright planetary like M57 is easier. Sort by size alongside magnitude when choosing targets.