M4

  
 
 
Home
New Images
Galleries
    Auroras
    Chrono Film
    Chrono DSLR
    Clusters
    Galaxies
    Nebulas
    Misc.
    Pool
Equipment
Links
Credits
 
   
 
  • RA: 16:23.6
  • Dec:  -26:32
  • Magnitude: 5.6
  • Size: 36.0 arc min
  • Distance: 7200 ly
  • Constellation:  Scorpius
  • Scope: 8" SCT at f/10
  • Autoguider: ST-4 faint mode
  • Sky conditions:  Very good seeing and transparency.
  • Film: Kodak Supra 400
  • Exposure: 2 x 30 minutes
  • Date:  May 9,2002 and April 14, 2005
  
 
Comments:  Both nights were clear and somewhat cold night for the season with a low in the upper 30s.  In 2002 the wind was about 10 mph so I had to hide behind a nearby glider school trailer.  M4 is one of the nearest globular clusters in the sky.  It displays a central "bar" structure, that is visible in the photo.  M4 is one of the most open, or loose, globular clusters.  It was discovered b De Cheseaux in 1745-46.  In 1987 the first millisecond pulsar was discovered in this globular cluster.  This pulser, 1821-24, is a neutron star rotating once every 3.0 ms which is 10 times faster than the Crab pulsar in M1.