Poretti Productions
Register - Login
 * Deep Sky Saturday, October 21, 2017
Deep Sky Images
Star Clusters
M3 - Globular Cluster

Previous
M3 - Globular Cluster

Enlarge to Full Size

Date: 5/20/2005
M3 in the constellation Canes Venatici is one of the most outstanding globular clusters, containing an estimated half million stars. At a distance of about 33,900 light years, it is further away than the center of our Galaxy, the Milky Way, but still shines at magnitude 6.2, as its absolute magnitude is about -8.93, corresponding to a luminosity of about 300,000 times that of our sun. M3 is thus visible to the naked eye under very good conditions - and a superb object with the slightest optical aid. Its apparent diameter of 18.0 arc minutes corresponds to a linear extension of about 180 light years

M3 has a compressed, dense core measuring 1.1' in diameter, or linearly, 11 light years, comparatively large for a globular. Its half-mass radius is 1.12', or about 11.2 light years, so that half of this clusters mass is contained in a volume of only 22 light years in diameter.

1st Light with the SBIG St-8i
May 20, 2005 - 2 days before full moon
Toronto, Canada
8" LX200GPS @ f/10
SBIG ST-8i
Baader Neodymium Sky Glow filter
15 x 20sec average combined/dark subtracted
No flats
CCDSoft, K3CCDTools, PixInsight, Photoshop

Back to Main

Melotte 15 (IC1805) SH2-126 / LBN437 M20 The Trifid Nebula DWB111 The Propeller Nebula IC1274 The Cone and Fox Fur Nebula NGC 2264

NGC1499 - The California Nebula M8 - Lagoon Nebula IC443 NGC1977 - The Running Man Nebula Elephant Trunk Veil East

Veil West Horse Head up Close Flame Nebula (NGC2024) Pelican Neck HSO Pelican Neck SHO Bubble Nebula

Pelican Nebula NGC6823 Pickering Triangle M27 M57 Rosette

Horsehead (up close) M42 Region Cone Nebula M1 from Kitt Peak Pelican and North American Nebulae IC5070 - Pelican Nebula in Cygnus

Veil West IC1396 IC 1311 in Cygnus NCG6914 NGC6992 - Network Nebula Butteryfly Nebula

M27 - *True* Colour M106 M33, the Pinwheel galaxy NGC 4565 (The Needle Galaxy) M74 from Kitt Peak NGC6791

M44 M92 M13 - Globular Cluster M3 - Globular Cluster

Astro Garage - Cog in the Machine