M 4 - GLOBULAR CLUSTER

SCORPIUS

 (ra: 16,23.6 / dec -26:32)

May 2009, in Collaboration Alejandro Tombolini from Próxima Sur 

Astro Pilar - Golfers Country Club, Pilar Buenos Aires, Argentina

DATA

TYPE: Globular Cluster

Apparent Magnitude: 5,9

Apparent Diameter: 26.3 arc minutes

DISTANCE: 7200 lights years

IMAGE INFORMATION

SCOPE: William Optics 132 FLT Triplet APO

CAMERA: SXVF H9

GUIDING: SBIG ST4 in Orion 100 mm refractor

IMAGE ACQUISITION: AstroArt 3.0

FILTERS: Astronomik Type II - Astronomik Ha 6 nm - Atik Filter Wheel

SKY CONDITIONS: transparency good and seeing very good

EXPOSURES: LRGB (16,16,16,16)

PROCESSING: Calibration in Images Plus, (Sigma Median Combine - no darks, flats, offsets -) CCD Sharp, Photoshop CS2

OBJECT DESCRIPTION AND IMAGE SESSION

Also known as the Black Eye Cluster. Is one of the loosen or less concentrated globular clusters in the sky. Catalogued as type IX due its star concentration. It is located at 1.3º west of Antares it can be seen with small telescopes (3.5 inches of aperture onwards). M04 would be  one of the most splendid globular cluster if it were not obscured by  black interstellar matter. (*)

My friend Alejandro was kind enough to let me work with his set up. I was surprised with the optics quality of this Telescope not to mentioned its fine termination. The mount was a Celestron CGE and after the three star align process showed a more than acceptable accuracy. Tracking and guiding response of the mount was quite smooth.

(*) Source Seds