M4

Located in the direction of Scorpius just 1.3 from Antares, it is the closest globular cluster to the solar system at just 6,000 ly distant, is approximately 70 ly across and has an unusual "bar" structure across the core. While close, its light has been attenuated by considerable dust and gas along the line of sight giving its stars a rich yellow-orange colour. Relatively metal-poor (ie contains few elements heavier than helium) it has a mass of about 8.4x104 solar masses. Classified, IX (loose towards the centre), on the Shapley-Sawyer globular cluster concentration scale (1927). 

 

Camera: SBIG STL11000M, Astrodon filters Scope: Takahashi TOA-130, f=1000mm, f7.7, fov 1.0 x 0.7
Mount: Takahashi EM-200 Temma 2 Guiding: internal
Filters/Exposures: R:G:B = 8:8:824m Location: ASV's LMDSS, Lady's Pass, Victoria, Australia
Date: July 2023 Processing: CCDStack2, RegiStar and Photoshop CS5