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Object Catalog

Filter and browse popular astrophotography targets from the Messier, NGC, and IC catalogs

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Seasonal Visibility

Objects are best when their constellation is highest in the sky

Where to Point

Four bright targets, found from stars you already know. From the Southern Hemisphere, Andromeda, Orion, and the teapot appear upside down.

Star-hop chart to the Andromeda Galaxy, M31 From Alpheratz, the corner of the Square of Pegasus, two stars along to Mirach, then two fainter stars toward Cassiopeia. M31 is the oval beside the second. Square of Pegasus Alpheratz Mirach M31 Cassiopeia

Andromeda, M31 Sep–Nov

From Alpheratz, follow the line of stars away from the Square of Pegasus to the second, Mirach. Turn toward Cassiopeia and hop two fainter stars. The galaxy is the faint oval beside the second. A 200 mm lens is enough.

Finder chart for the Orion Nebula, M42 Orion, with the three belt stars in a row. The sword hangs below the belt as a short line of three stars. The close-up shows the fuzzy middle one, which is the nebula. close up Betelgeuse Rigel belt sword M42

Orion Nebula, M42 Dec–Feb

Find the three belt stars. The sword hangs below the belt, or above it from the Southern Hemisphere. Its fuzzy middle star is the nebula.

Finder chart for the Lagoon Nebula, M8 The Teapot of Sagittarius. From the tip of the spout, straight up about six degrees into the Milky Way, is the Lagoon Nebula. Teapot spout M8 Milky Way

Lagoon, M8 Jun–Aug

From the tip of the Sagittarius teapot's spout, go about three fingers at arm's length where steam would rise. The Lagoon is the bright knot in the Milky Way there.

Finder chart for the Carina Nebula The Southern Cross with its two bright pointers on the left, the larger False Cross on the right, and the Carina Nebula about halfway between them along the Milky Way. Southern Cross pointers False Cross Carina Nebula Milky Way

Carina Nebula Dec–Feb

Southern sky. About halfway between the Southern Cross and the False Cross, in the Milky Way. The False Cross is larger and dimmer, with no bright pointers beside it.

Polar Alignment

A tracker only follows the sky when its axis points at the celestial pole

Finding Polaris and the north celestial pole The two stars at the front of the Big Dipper's bowl point to Polaris, about five times their spacing away. Close up, Polaris sits less than one degree from the true pole, shown against the full Moon for scale. close up Big Dipper pointers Polaris Polaris pole full moon for scale
North: the two stars at the front of the Big Dipper's bowl point to Polaris. Close up, Polaris sits less than 1° from the pole and circles it once a day.
Finding the south celestial pole Extend the long axis of the Southern Cross, and draw a line square to the two pointers from the point midway between them. The two lines cross about three degrees from the pole. Southern Cross pointers south pole
South: there is no bright pole star. The long axis of the Southern Cross and a line square to the pointers cross near the pole.
  1. Level the tripod.
  2. Set the mount's latitude scale to your latitude.
  3. Point the polar axis at the pole. In the north, Polaris is within 1° of it. In the south, use the Octans pattern that the mount's reticle or a sky app shows.
  4. Place Polaris, or the southern reference stars, where the reticle says for the current time. The star is not exactly on the pole.
  5. Shoot a 2-minute test at the focal length you will use.
  6. If stars trail in one direction, adjust and test again before the sequence.

Imaging Quick Reference

Recommended settings by object type

Object Type Sub-Exposure ISO / Gain Total Integration Key Tip
Bright Nebulae
M42, M8, M17		 30s – 2min 800 – 1600 1 – 3 hours Bracket exposures for bright cores. HDR blend short + long subs.
Faint Nebulae
NGC7000, IC1805		 2 – 5min 1600 – 3200 4 – 10 hours Narrowband filters (Ha, OIII) dramatically improve contrast.
Planetary Nebulae
M27, M57, NGC7293		 1 – 3min 800 – 1600 2 – 5 hours Small targets — use longest focal length you can. OIII filter helps.
Galaxies
M31, M51, M81		 2 – 5min 800 – 1600 4 – 10 hours Precise tracking critical. Dark skies essential for faint arms.
Globular Clusters
M13, M5, M22		 15s – 1min 400 – 800 30min – 2 hours Short subs prevent star bloat in the core. Easy beginner targets.
Open Clusters
M45, M35, M44		 30s – 2min 400 – 800 1 – 2 hours Wide field lenses work well. M45 reflection nebulosity needs longer subs.
Supernova Remnants
NGC6960, M1		 2 – 5min 1600 – 3200 5 – 15 hours OIII filter essential for Veil Nebula. Long integration reveals filaments.

Gear Recommendations by Difficulty

Level Typical Setup Focal Length Tracking
Beginner Camera + telephoto lens on star tracker 50 – 200mm Star tracker (Sky-Watcher, iOptron)
Intermediate Camera + dedicated astro lens or small scope 200 – 600mm EQ mount with autoguiding
Advanced Cooled astro camera + telescope 500 – 2000mm+ EQ mount with autoguiding + narrowband filters

Light Pollution: Bortle 1–3 skies are ideal for galaxies and broadband imaging. Narrowband filters (Ha, OIII, SII) enable imaging from Bortle 5–7 suburban skies. See the Bortle Scale reference in the Night Sky Planner.