CHAPTER 12: Observing Deep-Sky Objects

A Big-Bang Explosion of New Deep-Sky Books

There is a vast new library of deep-sky observing guides out these days, as the Recommended Reading page for Chapter 12 shows. Here are some capsule reviews of some current favourites, amid a huge explosion of deep-sky observing guides.

  The Night Sky Observers’ Guides
by George Kepple and Glen Sanner, et al

In Chapter 12 we praise the 2-volume Night Sky Observer’s Guides. That set is now a 3-volume work, with the addition of Volume 3: The Southern Skies, by Ian Cooper, Jenni Kay and George Kepple. At last, we have a thorough guide to the deep-sky targets of the southern hemisphere, to take the place of the wonderful but out-of-print Hartung’s Astronomical Objects for Southern Telescopes.

The new book follows the format of the previous volumes, surveying constellation by constellation just about all the double stars and deep-sky objects worth looking at in amateur telescopes. One of the original authors, George Kepple, teams with Australian Jenni Kay and New Zealander Ian Cooper to provide descriptions of hundreds of deep-sky objects. Finder charts are provided, as well as photos of many objects. The six detailed charts of the Large Magellanic Cloud are worth the price of admission alone. (The SMC gets one chart all to its own.) Available from Willmann-Bell, Inc.

  Atlas of the Messier Objects: Highlights of the Deep-Sky
by Ronald Stoyan et al

In an era of cost-cutting it is wonderful to see such a lavish book published about such a specialized subject, but one central to the backyard astronomer — the Messier objects. This is a coffee-table extravaganza of a book. Big pages (all 370 of them) and big, first class photos, many by top European astrophotographers, highlight the book. But this is certainly not just a picture book. It is packed with what must be the most complete and authoritative guide to the 110 objects in Messier’s catalog that has ever been printed. Following European tradition (the book was first published in Germany), the book does recognize a full 110 objects and explains why.

The book reviews the history of Charles Messier’s catalog, providing an excellent biography of Monsieur Messier with facts and insights new to everyone I’m sure. (I had no idea Messier used a telescope as large as 12-inches! Nor that Messier’s Parisian sky may not have been that dark.) The inclusion of other little-known catalogs of the day, by Lacaille, Bode and others, is wonderful and helps us see Messier’s work in historic context. 

Each Messier object is given at least 2 to 4 pages of text, with each object’s information divided into three headings: History (what earlier observers saw and wrote), Astrophysics (what we know today about the object), and Observation (what to expect to see through backyard telescopes). Most objects (nebulas and galaxies) are illustrated with fine eyepiece sketches by the author, so you do get a “reality-check” to balance the stunning color images.

This is an encyclopedic work. And that would be my only caveat. There are no star maps or finder charts here — though billed as an “Atlas” this book might best be described as an “Encyclopedia of the Messier Objects.” So don’t get it expecting a guide to use at the telescope. This is very much a tabletop reference work about the history and science of the best deep-sky objects. Amazon has it for $50 — a bargain. Published by Cambridge University Press.

The Battle of the Herschels

  Herschel 400 Observing Guide
by Steve O’Meara

If you’ve done the Messiers and it’s “Been there, Done that!” for all the showpiece workhorse objects, then you’re ready for the Herschels. As we explain on page 243 of The Backyard Astronomer’s Guide, William and Caroline Herschel went far beyond Messier and catalogued just over 2500 deep-sky objects, giving them H-numbers. Well, 2500 is a bit much to tackle. So observers have pared down the list a bit. Two of the finest deep-sky observers and authors give us their take on the best Herschels in two new books.

Steve O’Meara (as he is credited here, not the more formal Stephen James O’Meara of the author’s other books) presents another massive work following on from his popular Deep-Sky Companion series of observing guides that included the Messiers, the Caldwells, Hidden Treasures and Secret Deep, two collections of lesser-known but favourite targets of the author. In his volume, the Herschel 400 Observing Guide, O’Meara tackles all the objects on the official “Herschel 400” list as promoted by the Astronomical League. 

Objects are grouped by season, and night by night (for seven nights per month), grouping a set of adjacent objects, for example, as one night’s goal. This is a convenient way to manage 400 objects. Nicely done! Finder charts are provided, star-hopping directions, a B&W photo, and an excellent description of what to expect to see. All 400 objects get this treatment — the book is large and thick. It’ll work at the telescope but you won’t be able to hold this hefty book for long. Most finder charts for a night are grouped on one page, to aid in making photocopies for field use. Photos are of a similar scale making it possible to compare objects for size. 

Lest you think these are all targets for monster Dobs, the author compiled his observations with a trusty 4-inch refractor. But, remember, the author is Steve O’Meara and he lives in Hawaii! The rest of us mortals will need an 8- to 10-inch scope to do the Herschels well. And keep in mind these are northern sky objects — Aussies aren’t well served here, but then again William Herschel never went south — his son John did that!

  The Herschel Objects
by James Mullaney

Competing with O’Meara is James Mullaney’s slimmer, smaller and lighter paperback volume, The Herschel Objects. The author here takes a different approach. The book concentrates on descriptions of 165 selected “showpiece” targets from the Herschel catalog. And with Mullaney’s experience as an observer you can be sure these are wonderful and fascinating objects. But this is not the Herschel 400. Indeed, the author makes it clear he’s not happy with the Herschel 400 selection, though it was Mullaney who first suggested, in 1976, that culling the Herschels would make for a good, advanced list.

As Mullaney explains, he edited the catalog differently than did the original compilers of the Herschel 400. Mullaney tossed out all objects of William Herschel’s Class II and III (faint “nebulas” — galaxies in most cases), considering them too faint. His new book lists all the remaining 615 objects, and provides details on 165 of those. However, tossing out all Class II and III targets is a bit drastic, cutting out some nice objects. So Mullaney gives in and provides descriptions of 18 of those — such as NGC 6781, a big and easy planetary nebula in Aquila, and NGC 404, the little elliptical galaxy hiding in plain sight next to Beta Andromedae. 

Mullaney provides no finder charts (observers would likely be using other charts anyway) and photos only of selected objects. Though sparser in treatment, The Herschel Objects represents an excellent way to delve into the Herschel list. If 400 seems too daunting, then try Mullaney’s 165. Coming from James Mullaney, this is an excellent culling, one I wish I had programmed into my Go To telescopes. It is WAY better then the Caldwells! (But again, keep in mind that list is northern sky-only.)

  The Complete Guide to the Herschel Objects
by Mark Bratton

The book is well-titled – this is the complete guide. The result of a massive observing campaign by Canadian amateur astronomer Mark Bratton, this monster 600-page book provides descriptions and data on all 2500+ objects in William Herschel’s original General Catalogue. Illustrations are B&W images from Deep-Sky Survey plates or sketches from the author, so the illustrations better reflect what the object is likely to look like. No enhanced colour Hubble images here. A hallmark of the book is Bratton’s thorough coverage of the history of the Herschel’s and their telescopes. Covering 2500 objects in one book means the descriptions (like logbook entries) of each object are of necessity brief but in most cases more than sufficient. A monumental work, and essential for the Herschel devotee.

If you are going after the Herschel list, be sure to also pick up a copy of the new Cambridge Atlas of Herschel Objects (pictured above), a reworking of the excellent Cambridge Star Atlas but with all 2500+ objects labeled with their original Herschel numbers. Compiled by James Mullaney, it also contains data on his selected best 200+ objects. 

Battle of the Personal Observing Guides

  Deep-Sky Wonders
by Sue French

Based on Sue French’s ongoing and excellent deep-sky observing columns in Sky and Telescope magazine, this latest compilation of articles is massive and marvellous. This is a 320-page deluxe coffee table book you aren’t likely to be taking to the telescope with you, but it is great for planning a nights’s viewing. The book includes 100 tours of selected regions of the sky. Of those, 23 tours were published before in the smaller work Celestial Sampler, while 77 are new tours derived from more recent columns. The tours provide a wide range of objects, from small-scope showpieces to large-scope challenges. Each tour describes 6 to 12 targets, and has small star maps to aid in locating them. Sue French has a talent for digging out interesting but obscure targets so even the die-hard deep-sky fan will find much to explore here. The book will be overwhelming for the beginner but is ideal for the intermediate observer wanting to go beyond the basic Messiers, and has an 8-inch or larger telescope. The book is lavishly illustrated and printed. At $40 it is a bargain. 

  Hidden Treasures   and   The Secret Deep
by Stephen James O’Meara

In the last two volumes of his Cambridge Deep Sky Companion series, master deep-sky observer O’Meara selects 109 objects for each of two similar volumes, targets not in the Messier or Caldwell catalogues. Most of the objects described in Hidden Treasures and The Secret Deep are “finest NGC” objects, but many are from more obscure catalogs. All are unique targets worthy of tracking down. For example, object #1 in The Secret Deep is van den Bergh 1, a reflection nebula just off Beta Cassiopeiae, making it dead easy to find but little known to most observers. All objects have B&W photos and finder charts, and are described with the well-researched scientific authority yet personal poetic touch that is O’Meara’s trademark. And an excellent trademark it is! Observers of all skills will find a lot of rewarding targets here, though these volumes are best described as being suited to the intermediate or advanced observer. 

  Cosmic Challenge
by Philip Harrington

This personal observing guide is billed as “the ultimate observing list for amateurs.” A bit of hyperbole perhaps but this is an eclectic and far-ranging list. Author Harrington includes 188 objects (not all deep-sky) from naked eye targets to really faint big-scope prey. The common factor is that for every instrument level (he breaks the list down into six aperture ranges) the objects can all be considered challenges. So Messier 81 is here, not as a showpiece object for moderate telescopes but as a challenge for naked eye viewers. M32 and M110, the companions to the Andromeda Galaxy, are binocular challenges. M33 is included both as a naked eye challenge and as a large scope challenge for all its small nebulas. Pluto is a small scope challenge, while splitting Pluto and Charon (few have done it) is a monster scope challenge. Other lunar and planetary targets are included so this is not just for deep-sky observers. Small star maps and sketches are included. While many “easy” targets are included, this is book more for experienced observers looking to pick off personal observing challenges, perhaps for bragging rights for seeing M81 naked eye, for example. It’s an interesting twist on a personal observing guide. Up for some challenges? Let Phil show you the way.

  1001 Celestial Wonders To See Before You Die
by Michael E. Bakich

Taking his cue from other “bucket list” travel guides, Astronomy magazine editor and deep-sky expert Michael Bakich provides his selection of no less than 1001 deep-sky targets you must see. With 1001 targets on offer, even with 500 pages to do it, most get brief descriptions and only a few get illustrations. None get finder charts but any good observers will have charts in abundance. While lots of showpiece objects are here inevitably most will be second and third tier objects, and the book makes little distinction on the suitability of various objects for different apertures and observers’ skills. You have to read the text to learn if the object is one to put on your list for the night. Objects are broken down by month and then by right ascension, making it difficult to sort what objects might be grouped in the same area of sky for easy picking. The sky tour method of Sue French’s book is more user friendly. However, Bakich does cover the whole sky, including many southern hemisphere targets on his bucket list, which really should be standard now in any observing guide. Observers who haven’t been south really can’t call themselves deep-sky experts if they haven’t seen what are arguably the best examples of most deep-sky objects. So bravo to Bakich for being all-sky inclusive.

  Treasures of the Southern Sky
by Robert Gendler, Lars Lindberg Christensen, and David Malin

While this is not an observing guide per se, I include it here as our book’s Chapter 12 does contain a major section on southern sky observing. This new coffee table book features big and beautiful images of many of the showpiece objects of the southern hemisphere sky. It will certainly serve as an introduction to the main choice targets to include on your southern sky bucket list. Photos are a mix of images taken or processed by astrophoto master Rob Gendler, along with professional images from the European Southern Observatory and from Hubble. Many will be familiar to amateur astronomers. However, this is picture book and is not meant to be a thorough guide or atlas to southern sky viewing. Many high-priority southern sky targets are not included while objects well-known to northern observers such as the Orion Nebula and Lagoon Nebula are. The Magellanic Clouds get pretty brief coverage. This is a good book for an astronomer’s Christmas present. 

  The Cambridge Photographic Star Atlas
by Axel Mellinger and Ronald Stoyan

Photographer Axel Mellinger shot the entire sky in a massive 3000-image mosaic, reproduced here in sections in atlas format. Every area of sky is accompanied by a chart labelling all the deep sky objects visible in the large-scale images. The photos depict the sky at a scale of 1° per cm, and record stars down to 14th magnitude. This is by far the best photo atlas yet and is ideal for photographers to help them identify features in their wide-angle images of the Milky Way and night sky. Unfortunately, the photos suffer from being a little too dark on the page and the nebulas not brought out enough in processing to really stand out. Nevertheless, this is the modern equivalent to E.E. Barnard’s historic Atlas of Selected Regions of the Milky Way.

  Deep-Sky Observing Guides @
by Alvin Huey

Owners of big Dobs will want these! Alvin Huey has put together some great guides to a host of faint and challenging targets, formatted in pages that are easy to use at the telescope. Wide-angle charts, finder charts, and photos all help in locating and identifying oodles of deep-sky objects suitable for big-aperture scopes. Best of all — they’re free! You can download them at 

Included in the free guides are:
The Local Group of some 40 galaxies, plus globulars and nebulae in M31 and M33
Selected Small Galaxy Groups of about 60 galaxy groups, mostly involving Messier and NGCs
Selected Galaxy Trios of about 115 galaxy triplets, most of NGC objects
Selected Shakhbazian Galaxy Groups of 60 faint, tiny galaxy groups more challenging than Hicksons!
Abell Galaxy Clusters charting 80 Abell clusters and their myriad members
Globular Clusters with charts for all globulars above -50° declination, including the faint and obscure
Planetary Nebulae with charts for 350 planetaries and supernova remnants above -50° declination

These are massive and well-presented guides, clearly designed for use at the telescope. The sample images at right show facing pages from the Galaxy Groups guide, showing the finder charts and identifying photo for galaxies around M106, a favourite field of mine.

The guides are PDFs which you can print yourself as needed, or take to a print shop to have made into bound books.

Now, if those free books aren’t enough, Huey also sells three excellent and even more comprehensive guides aimed at the really-deep-sky observer:

Hickson Group Observer’s Guide to all the galaxy groups in Paul Hickson’s catalog (sample pages below)
Abell Planetary Nebulae Observer’s Guide to all the Abell planetaries
Observing the Arp Peculiar Galaxies,
listing all the entries in Halton Arp’s catalog of odd galaxies

Each is available for purchase as printed books from the author’s website.
If you’ve got a big scope and dark skies, these books will keep you going 
for years of observing “on the edge.

— Alan Dyer, January 2012

See Chapter 12’s Recommended Reading page for publication details of these and other books.
See the Chapter 2  for reviews of new binocular observing guidebooks and Chapter 11 for recommendations on Atlases.