The Vixen 55 mm meets M57 and Some Globulars

1998 Apr 27

I hadn't intended to do any more Messier hunting with my Vixen 55 mm fluorite for a while. Yet on the evening of 27 April, 1998, clear sky tempted, and work had been frustrating, so I hauled the little telescope out into my yard in Palo Alto, California. I looked at M57 and some early summer globular clusters.

M57 had barely cleared the treetops when I started hunting for it. With a 12 mm Brandon eyepiece for 37x, it was a difficult target, though things improved as Lyra rose higher and as the neighbors across the street finally turned out their porch light. I could see the object at 37x, but it took 55x (8 mm Brandon) and averted vision to detect the opening in the ring.

The globulars were a surprise. At 37x, M5 was the best object, showing a hint of graininess, whereas M13 and M92 did not. I am not convinced that this quality is really incipient resolution of stars -- though it might be. It seems equally possible that what I am on the edge of seeing is chance close associations of several of the cluster's stars along my lines of sight. The next easiest globular was M80 -- way down in Scorpio, and much easier than its bigger neighbor, M4, which was almost lost in the haze. M10, M12, and M14 were all harder still, and hard to find -- I always seem to get lost in central Ophiuchus. Toughest of all was M107, but it was there.

When M3 gets away from the zenith (it's hard to work that area with my altazimuth mount) and M13 gets higher, I shall investigate the resolution of globular clusters with the little Vixen, in more detail.

Jay Reynolds Freeman; 1998 Apr 28