Object: Open cluster RU 173                     Constell: CYG

RA: 20h 41.8m           Decl: +35° 33'          Epoch: 2000
Mag:                    Size: 50'               Type: III 3 p

Observer: Jere Kahanpää
Obs. place: Jyväskylä, Finland
Date/Time:  5./6.8.1996, 00.15

Telescope: N 205/1000
Magn: 25x               Filter:
Field: 90'              NE Lim.mag: 5.0m 
Background sky: 5       Seeing: 3-4
Weather: 1/2 Moon low E, bright NLC N.

Brightness: 1           Alt:    
Description: Easily visible with a 6x30 finderscope as 2 stars +
a bright glow. 25x: Diameter about 1/2 of the field = 45'. About
30 stars to magnitude 11.5. The brightest stars surround an
almost starless rond spot. This gives the cluster a somewhat
ringlike outline. Ring diam. 30'. Slightly concentrated.