Not long ago I bought a new binocular, the Orion Ultraview 10x50 that I reviewed in a recent posting. I had intended to use it primarily for bird-watching -- the 7x35 Tasco that I keep under the front seat of my car for that purpose is wonderful, but occasionally I want more magnification. Yet I had the binocular with me at Fremont Peak last weekend, so of course I looked at a handful of astronomical objects, and I had so much fun that I decided to try a full Messier survey.

I have done Messier surveys with small instruments before; indeed, the first time I went through the Messier catalog was with a 7x50 binocular -- a Swift Commodore Mark II -- starting in about 1979. I do Messier surveys with most new instruments that come into my hands, as a way of familiarizing myself with equipment. I haven't done one with so small an aperture since, but I have gotten a lot more experience; close to 3000 different objects have entered my logbook, and the Messier survey with the 10x50 is my fifteenth.

I started out by looking at two of the Messier objects that many people find difficult with small apertures, planetary M76 and faint galaxy M74. The galaxy was easy with averted vision; it is easy to find, in the middle of a naked-eye asterism of four stars that mark the points of a 30-75-75 isosceles triangle with the sharp point cut off; the stars are eta, 101, 103 and 105 Pisces. I always find M76 by extending the line from 51 Andromeda to phi Persei and going a little to the side, but I have observed with reversed images as often as not, so I never am quite sure which side. By the time I got that straightened out it was quite clear, however, that I could see M76 with the UltraView. I looked casually at the big open clusters M36, M37 and M38, just risen, and noted a faint wisp of the Merope nebula visible in M45, the Pleiades.

The next night, I went exploring in the Sagittarius area. Hunting Messier objects in the central Milky Way with a decent binocular is enough to make you feel like Jack the Giant Killer; they are all easy to find and easy to identify, and some fields have half a dozen or more. I had no real difficulty with the southerly globular clusters M54, M69 and M70; their proximity to horizon glow sometimes makes them difficult to identify as non-stellar at low magnification -- I had a lot of trouble with them in the 7x50. All the rest of the stuff in that area was very easy. M22 was probably the most impressive, a big snowball next to Jupiter, but M55 -- perhaps the ghost of a snowball -- was also neat to look at.

Messier views in a binocular are qualitatively different from those in a larger telescope. Most galactic clusters show at least a granular appearance, and some are well-resolved. Globulars and galaxies are mere smudges; only the largest show any trace of detail. Diffuse nebulae show well at the large exit pupils of binoculars, but rarely with detail.