M 26

This cluster is not so impressive as its apparent neighbor, M11, and Messier even noted that it was "not distinguished in a 3.5 foot (FL) telescope and needed a better instrument".

Nevertheless, this is a tight, beautiful cluster with brightest stars of mag 11.9, spectral type B8. Burnham mentions about 25 stars visible in 6-8 inch scopes and about 70 fainter members, Mallas/Kreimer overall 90. Its diameter of 22 light-years appear as 15 arc minutes from the 5,000 light years distance. The Sky Catalogue 2000 gives a calculated age of 89 million years for this cluster.

As Kenneth Glyn Jones mentions, James Cuffey of the Kirkwood Observatory, Indiana University, reported that a striking feature of this cluster is a well-defined zone of low star density in a region of diameter 3'.1, immediately surrounding the nucleus. It is more probable that this region is obscured by dark interstellar matter than that it is a real "hole" in the stellar population.

Right ascension	18 : 42.5 (hours : minutes)
Declination	-09 : 27 (degrees : minutes)
Distance	5.0 (light-years*10^3)
Visual magnitude	9.3