M3: a magnificent globular cluster

This is one of the brightest globular clusters in the sky, barely visible even to the naked eye. From 32,000 light years its half a million stars appear as a faint glow in visual observation. The bright resolved stars are all giants; main sequence stars are all too faint to show up.


New:




Images taken: May 1, 2006, by Ruth Mauldin and Jenzy Wunder.

Telescope: Meade 12 in with f/5.6 focal reducer (f=67in), guided on a 8.4 mg star.

Camera: SBIG ST-7 CCD

The arrows indicate RR Lyrae variables identified inside the cluster.

Seeing: 2.5 as.

Exposures: 20 min red, 20 min green, 2x20 min blue (1h20m total).


Image processing: CCDoops + CCDSoft + CCDsharp + Photoshop CS.