For Asteroids, Comets, Meteor showers, Satellites, and time-sensitive trackers:

Go to Observing & Sky Events→

Books on Astrophotographic Target Selection

The 100 Best Astrophotography Targets by Ruben Kier - This excellent list of classic targets is a great resource when trying to pick what you are going to shoot next. (Thanks to Vaughn Payne for suggesting this one!)

The 750 Best Deep Sky Objects (Gary Imm) – A ranked, imaging-friendly deep-sky target list designed to make “what should I shoot next?” decisions fast.

The Top 250 Planetary Nebulae: A Guide for Astrophotographers (Gary Imm) – A curated “best-of” list of planetary nebulae selected specifically for astrophotographers.

The Complete Messier Catalog: Plus Caldwell Catalog Highlights (Gary Imm) – A practical “classic targets” reference: Messier plus selected Caldwell highlights for imagers.

The Complete Sharpless Catalog: 313 (Mostly) Amazing Objects for the Astrophotographer (Gary Imm) – An imaging-oriented guide to Sharpless emission-nebula targets gathered into one place, useful for structured target planning.

The Complete Arp Catalog: A Guide for Astrophotographers (Gary Imm) – A practical guide to Arp peculiar galaxies, aimed at research-driven target selection and framing.

The Complete vdB Catalog (Gary Imm) – An imaging-oriented guide to the vdB reflection nebulae, useful when you want lesser-known but rewarding targets.

The Hickson Catalog (Gary Imm) – Hickson Compact Groups presented as advanced galaxy targets for imagers who want dense, high-interest fields.

Galaxies and Their Amazing Features (Gary Imm) – A feature-driven galaxy targeting guide that helps you choose subjects based on distinctive structures worth imaging.

The Wonders of the Heavens: Volume 1 (Gary Imm) – A themed collection of notable objects intended to spark new target ideas when you want variety.

Beautiful Space Objects – Volume 1 (Gary Imm) – An inspiration-forward collection of visually compelling targets for quick “what should I image next?” decisions.

The Night Sky Observer’s Guide (Vols. 1–3) – A constellation-by-constellation guide to thousands of deep-sky objects with charts, descriptions, sketches, and photos; excellent for choosing and prioritizing targets.

The Astrophotography Sky Atlas – A compact atlas built for imagers, with deep-sky targets plotted by true size/shape plus an index that helps you match targets to season and field of view.

The Astrophotography Planner (Second Edition) – A planning guide that shows when top targets are best placed and how many quality imaging hours you can expect, with framing guidance to help you plan sessions efficiently.

Deep-Sky Companions: The Caldwell Objects – A detailed guide to the Caldwell list with rich object notes and background; a strong “next list after Messier” for selecting showcase targets.

Deep-Sky Companions: Hidden Treasures – A curated list of lesser-known deep-sky gems with observing notes and finder help, ideal when you want new targets beyond the usual lists.

Cosmic Challenge – A themed set of observing “challenges” with difficulty ratings and finder charts; great for discovering unusual or demanding deep-sky targets.

Galaxies and How to Observe Them – A galaxy-focused guide combining background, observing technique, and curated galaxy targets to support more deliberate target selection.

Nebulae and How to Observe Them – A practical nebula guide with observing strategy, filter guidance, and extensive target coverage across nebula types.

Planetary Nebulae and How to Observe Them – A PN-centric guide with technique and a substantial set of described targets, useful for building a structured PN target list.

Steve O’Meara’s Herschel 400 Observing Guide – A structured path through the Herschel 400 list with practical notes and charts—excellent for selecting “next level” deep-sky targets after Messier/Caldwell.

Deepsky Object Catalogs

Overview of Deepsky Catalogs

Messier & Other Catalogs – Paris Observatory – Handy table summarising all major deep-sky catalogs.

SIMBAD Dictionary of Nomenclature – Master lookup of every published designation for celestial objects

Messier Catalog

NASA / Hubble Messier Catalog – High-resolution Hubble images and object facts for all 110 Messiers.. NASA does the Messier list with some of the best images ever taken of each object! Descriptions and some finder charts (somewhat crude but useful).

Seasky.org – Messier Guide – Descriptions, finder charts, and observing tips.

Go-Astronomy – Messier Objects – Whole-sky map with images, data, and cross-references. - nice whole sky map, descriptions, and images.

Spanel Planetarium Messier List – Illustrated Messier tour from Western Washington University.

SEDS Messier Database – Classic Messier pages with images, discoverer notes, and catalog cross-links.

in-the-sky.org – In-The-Sky.org’s interactive Messier catalog with data, coordinates, and visibility charts for all 110 Messier objects (filterable by constellation, object type, etc.).

skyatnightmagazine.com – BBC Sky at Night magazine’s complete Messier Catalogue, including images, descriptions, magnitudes and coordinates for finding each object 

Messier Catalog – AstroPixels – Comprehensive table listing all Messier objects with classifications, magnitudes, and coordinates, plus links to a photo gallery project.

Messier Catalogue – FreeStarCharts – Overview of all 110 Messier objects, including descriptions and observing tips for amateur astronomers.

NGC/IC Catalogs

Wikipedia – Full NGC List – Clickable master list with basic data and images.

In-The-Sky.org – Interactive NGC Catalog – Object data plus visibility charts for your location.

SEDS NGC/IC Database – Searchable NGC/IC entries with historical notes. cross-links to more data.

Sky-Map.org – IC Image Browser – IC catalog list linked to multi-survey images. (Warning: not a secure site)

Emil Ivanov – NGC Photo List – Amateur images and notes for many NGC objects.

Emil Ivanov – IC Photo List – Companion gallery for IC objects.

ngcicproject.observers.org – The NGC/IC Project (archived): a comprehensive database aiming to correctly identify all original NGC and IC objects, with collected images and detailed data for each entry 

NGC 2000.0 – HEASARC – Modern compilation of the New General Catalogue and Index Catalogues with updated positions and corrections.

NGC / IC Catalogues – FreeStarCharts – Detailed information on the NGC and IC catalogs, including object types and historical context.

Arp Catalog

NASA/IPAC – Arp Atlas of Peculiar Galaxies – High-resolution scans of Halton Arp’s 1966 atlas with notes on each interacting or disturbed system.

https://arpgalaxy.com/ - A great overview of the ARP’s Catalog and some great cross-links to images and more info.

Bernards Catalog

Barnard Catalogue (In-The-Sky.org) – In-The-Sky.org’s online listing of Barnard dark nebula objects—one of the few easily browsable Barnard catalogs available on the web.

saguaroastro.org – Saguaro Astronomy Club: “The Best of Barnard’s Dark Nebulae” observing list, featuring data and notes for many of the most famous dark nebulae from E.E. Barnard’s catalog 

Barnard Dark Nebulae Catalogue – DeepSkyCorner – Detailed descriptions and data for Barnard dark nebulae, including object numbers and coordinates.

Caldwell Catalog

NASA / Hubble Caldwell Catalog – Stunning Hubble views of the 109 Caldwell objects with finder info.

Wikipedia – Caldwell Catalogue – Table with object data, discovery details, and links.

in-the-sky.org – In-The-Sky.org’s interactive listing of the 109 Caldwell objects, with data on each object and tools for viewing visibility from different locations. 

Caldwell Catalog – AstroPixels – Detailed table of all Caldwell objects with classifications, magnitudes, and coordinates, plus links to a photo gallery project.

Caldwell Catalogue PDF – Scribd – Downloadable PDF listing all Caldwell objects with descriptions and observing data.

DWB Catalog

The Cygnus X Region: Catalogue and Study of Emission Nebulae (1969, A&A) – Classic Astronomy & Astrophysics paper on the Cygnus X region, including a catalog of studied emission nebulae and related observational results.

Herschel Catalog

“The Herschels and Their Catalog” (PDF) – Illustrated history of William & Caroline Herschel’s surveying work.

Wikipedia – Herschel 400 Catalogue – Detailed object table with cross-references to Messier & NGC.

Go-Astronomy – Herschel 400 List – Online reference with sortable data and sky map.

Herschel’s General Catalogue (1864) – Archive.org – Original scanned catalog of nebulae and clusters.

Royal Society – Herschel Catalog Scans – PDF facsimiles of Herschel’s 1786, 1789, 1802 nebulae papers. The complete online text of “A general catalogue of nebulæ and clusters of stars, arranged in order of right ascension and reduced to the common epoch 1860.0 (with precessions computed for the epoch 1880.0)” by Herschel, John F. W. (John Frederick William), Sir, 1792-1871

Catalogue of One Thousand New Nebulae & Clusters (1786 PDF) – William Herschel’s first great nebula catalog (Philosophical Transactions vol. 76 pp. 457-499) scanned in full! A downloadable Scan of "Catalogue of One Thousand New Nebulae and Clusters of Stars" (PDF). By William Herschel. Philosophical Transactions of the Royal Society of London. 76: 457–499. Bibcode:1786RSPT...76..457H

Catalogue of a Second Thousand of New Nebulae (1789 PDF) – Herschel’s follow-up paper adding another 1 000 objects and remarks on the heavens’ structure. A downloadable scan of the "Catalogue of a Second Thousand of New Nebulae and Clusters of Stars; with a Few Introductory Remarks on the Construction of the Heavens", by William Herschel. Philosophical Transactions of the Royal Society of London. 79: 212–255. Bibcode:1789RSPT...79..212H. doi:10.1098/rstl.1789.0021.

Catalogue of 500 New Nebulae & Clusters (1802 PDF) – Third installment listing 500 more nebulae, including planetary nebulae, with construction-of-the-sky commentary. A downloadable scan of "Catalogue of 500 New Nebulae, Nebulous Stars, Planetary Nebulae, and Clusters of Stars; with Remarks on the Construction of the Heavens", By William Herschel. Philosophical Transactions of the Royal Society of London. 92: 477–528. Bibcode:1802RSPT...92..477H. doi:10.1098/rstl.1802.0021.

Catalogue of One Thousand New Nebulae and Clusters of Stars (William Herschel) – PDF – Cleaner PDF scan of William Herschel’s historic catalog paper describing 1,000 newly recorded nebulae and star clusters.

Second-Thousand Catalogue (clean scan, PDF) – High-resolution copy of the 1789 paper suitable for printing or detailed study. It's a cleaner downloadable PDF of “Catalogue of a Second Thousand of New Nebulae and Clusters of Stars; With a Few Introductory Remarks on the Construction of the Heavens. By William Herschel, L L. D. F. R. S.” from Herschel, William, Public domain, via Wikimedia Commons.

Catalogue of Nebulae & Clusters of Stars (1863 PDF) – Sir John Herschel’s consolidated catalog (2 510 objects) that became the basis for the NGC; full 1863 scan.

Herschel 400 Guide – Part I (PDF) – Observing charts and object notes for the first 134 entries of the Astronomical League’s Herschel 400 program.

Herschel 400 Guide – Part II (PDF) – Continuation covering objects 135-267 with finder charts and data.

Herschel 400 Guide – Part III (PDF) – Final volume (objects 268-400), completing the full Herschel 400 observing guide.

Astronomical League – Herschel 400 Program – the official observing program page for the Herschel 400, providing the full list of 400 deep-sky objects (a subset of the Herschels’ discoveries ) along with program details and resources for observers.

Herschel 400 Observing Guide – Cambridge University Press – Guidebook providing detailed information and observing tips for the Herschel 400 catalog.

Hickson Compact Groups

HCG List – Wikipedia – Table of all 100 Hickson groups with positions, redshifts, and member counts.

LBN Catalog

Catalogue of Bright Nebulae (Beverly T. Lynds, 1965) – PDF Mirror – Same paper in a straightforward PDF format, useful for quick downloading/printing.

LDN Catalog

Go-Astronomy – LDN List – Complete coordinates and sizes for all 1,700 Lynds Dark Nebulae

PGC / LEDA

HyperLeda Database – Search 3 million galaxies by name, position, redshift, or diameter; returns detailed photometry and morphology.

Quasars

List of Quasars (Wikipedia) – Wikipedia’s curated list of notable quasars, useful as a quick reference and jumping-off point for further research.

MILLIQUAS: The Million Quasars Catalog (v8) – HEASARC access point for the MILLIQUAS catalog, a large compiled database of known and candidate quasars for deeper target research.

Sharpless Catalog

Online Sharpless Catalog– Dedicated site with data, images, and observing notes on all Sh-objects.

GalaxyMap – Sharpless Objects – Interactive Milky Way map with Sharpless nebulae.

PDF Atlas of the Sharpless Catalog – 200-page atlas of Sh objects with charts and survey plates.

Neutral.org – Sharpless Comprehensive List – Data table with alternate IDs and images

Astro Neutral Orgs online Sharpless Catalog - This is a great comprehensive list of the Sharpless Catalog.

Wikipedia’s Sharpless Catalog – Overview of Stewart Sharpless’s catalog of 313 H II regions (emission nebulae), with a list of all Sharpless

objects and their basic data .

In-The-Sky.org – Sharpless Catalog – Interactive list of 313 H II regions with visibility charts for any observing site.

The Sharpless Catalog – Adventures in Deep Space – Overview and selection of notable Sharpless catalog objects with descriptions and observing notes.

The Local Group

FaintFuzzies PDF file of the Local Group - The galaxies consisting of our own Local Group!

Uppsala General Catalogue (UGC)

UGC Online (PDF Scans) – Digitised pages of the 12 921-object UGC with positions, sizes and magnitudes for northern galaxies.

vdB Catalog

Emil Ivanov’s vdB list – Nice reference.

vdB Catalog – Wikipedia – Table of 158 reflection nebulae with positions, magnitudes and cross-IDs.

Wolf-Rayet Stars

Galactic Wolf Rayet Catalog – The only online catalog of these stars I have found. Note: Brooweser may flag as unsecure link it seems to work okay.

Double Stars

Washington Double Star Catalog (USNO) – The definitive database of double and multiple stars, with positions, separations, magnitudes, and historical measurements for a massive number of systems.

Astronomical League – Double Star Observing Program – A curated observing program built around 100 excellent double and multiple-star targets, with guidance that makes it easy to get started and stay organized.

Quasars

Wikipedia – Quasar – Detailed reference on quasar properties, discovery, and cosmological relevance.

RASC – Visually Observing Quasars (PDF) – Guide to identifying and observing bright quasars with amateur gear.

Wikipedia – List of Quasars – Catalog of notable quasars with coordinates and finder info.

Supernova

Rochester Astronomy – Bright Supernovae – Daily-updated list of current supernova discoveries with finder charts. Unique resource with the latest Supernova reports.

IAU Transient Name Server (TNS) – Official, up-to-the-minute database of newly discovered supernovae and other transients.