110 Deepsky Highlights

While many organizations have "top 100" lists, the 110 Deepsky Highlights refers to a specific modern database curated to be the "Ultimate Messier Alternative." It is most famously associated with the RASC (Royal Astronomical Society of Canada) as their "Deep-Sky Gems" or "Finest NGC" list, often rounded or modified into a 110-object challenge to mirror the numerical count of the Messier catalog.

Here is the story behind this "best of the rest" collection.

History & Who Made It

The most influential version of this list was compiled by Alan Dyer, one of the world’s most respected astrophotographers and astronomical authors, in the mid-1990s.

Dyer realized that while the Messier list is the "Gold Standard," it is geographically biased (Messier couldn't see the far south) and includes several faint, "boring" objects while ignoring spectacular ones. Dyer selected 110 objects that are, in many cases, more visually impressive than the Messier objects, specifically for the RASC Observer’s Handbook.

The Purpose: The "Better than Messier" List

The purpose of the 110 Highlights is to provide a balanced "Tour of the Universe."

• Visual Appeal: Every object on this list was chosen because it has "character"—a unique shape, a striking color, or a fascinating structure.

• The 110 Symmetry: By keeping the list at exactly 110 objects, it allows clubs to host "Alternative Marathons." Instead of the standard Messier Marathon, observers try to find all 110 Highlights in a single night.

• Modern Equipment: While Messier used a small, poor-quality telescope, this list assumes a modern 4-inch to 10-inch telescope, allowing for slightly fainter but much more detailed targets.

What Objects Can Be Found In It?

The 110 Highlights act as a bridge between the "beginner" Messier objects and the "expert" Herschel 400. It is a diverse mix that covers the entire northern sky and the upper parts of the southern sky.

The Breakdown (110 Objects Total):

• 45 Galaxies: Including the "Edge-on" Needle Galaxy and the "Interacting" Antennae Galaxies.

• 24 Open Clusters: Including the "Double Cluster" in Perseus and the "ET Cluster."

• 15 Planetary Nebulae: Featuring the "Ghost of Jupiter" and the "Saturn Nebula."

• 12 Bright Nebulae: Including the "North American Nebula" and the "Veil Nebula."

• 14 Globular Clusters: Including the massive NGC 5139 (Omega Centauri) for those far enough south.

The 110 Highlights Database (Flat Text Summary)

Catalog Name: 110 Deepsky Highlights (RASC Finest NGC) Creator: Alan Dyer / RASC Year Established: ~1995 Total Objects: 110 Primary Focus: Visual "Showpieces" of the NGC/IC catalogs

Object Category: Count

• Galaxies: 45

• Open Clusters: 24

• Planetary Nebulae: 15

• Bright Nebulae: 12

• Globular Clusters: 14

Top 5 "Must-See" Highlights:

1. NGC 869/884: The Double Cluster (The most famous objects Messier missed).

2. NGC 4565: The Needle Galaxy (The finest edge-on galaxy in the sky).

3. NGC 6960/6992: The Veil Nebula (A massive, delicate supernova remnant).

4. NGC 7293: The Helix Nebula (The closest large planetary nebula to Earth).

5. NGC 2392: The Eskimo Nebula (A high-magnification planetary nebula jewel).

Why It’s a Favorite

Observers love this database because it rewards you for your effort. If you look at a Messier galaxy, it might just be a smudge; if you look at a "Highlight" galaxy like the Needle, you see a sharp dust lane cutting through a sliver of light. It is the "Connoisseur's Choice" for a Friday night at a dark sky site.

Download