Planetary nebula and globular cluster in Sagittarius

  It makes for interesting observing when two different types of deep sky objects can be seen in the same telescopic field.  The Box Nebula is a fairly small planetary nebula with a curious rectangular shape.  It is also sometimes called the Little Gem Nebula, and it does have a bit of a gem-like appearance in this photo.  This object is about 4500 light years away.  Just 22 minutes of arc to its south (to the left in this picture) is the distant globular cluster NGC 6440.  (As a point of comparison, the apparent diameter of the moon is about 30 minutes of arc). 

Image details:  Mosaic based on 7 images of NGC 6440 and 9 images of NGC 6445, each 150 seconds at ISO 1600, taken with a Canon 400D camera through a Meade 12” telescope at f/10. 

September 2008