Basic object information
Object name: M 13
Popular name: Hercules Cluster
Object type: Globular cluster
Magnitude: 5.8
Size: 20.0'
Object classification: V
Description: !!eB,vRi,vgeCM,*11...
Notes: Hercules cluster;Messier said round nebula contains no star

Catalog information
RA (J2000.0): 16h 41m 42.0s
Dec (J2000.0): +36 28' 00"

Constellation: Hercules

Observer: Iiro Sairanen
Obs. place: Lakasenpelto, Imatra, Finland
Date/Time: 25/26.4.2008 1:15

Telescope: Newton 110/805 mm

Magn: 109x

Filter:

Field: 28'

NE Lim.mag: 5.0

Background sky: 5

Seeing: 4

Height: 56
Visuality: I
Weather: +2C, astronomical twilight, moist

This sketch has been made during the astronomical twilight and thru thin upper clouds. Familiar shapes were out of sight but there were still hundreds of individual stars visible and the globular was completely granular.