Nights at Melinda Heights

For a full size image click here.

Distance: 62,900 Light Years
Magnitude: 10.32
Size: 4 Arc Minutes
Cluster Type: Class VI
Telescope: RC 10” 2000mm FL
Camera: QSI 683
Mount: AP 1100
Exposure: L 18×180 Bin 1, RGB 15×90 Bin2

NGC 4147 is a globular cluster in the constellation Coma Berenices. This is a small and compact cluster that resides in the higher latitudes of our galaxy placing it in our galactic halo. NGC 4147 is not very bright when compared to the other 146 known globular clusters in our galaxy, in fact it ranks 112th brightest out of the 146. NGC 4147 is home to several variable stars, some red giants, and also some blue stragglers. However, not a lot is known about the quantities of variable stars in the cluster. At last count in 2005 there were 17 known variables plus another possible candidate. More recently, a renewed interest in NGC 4147 is surfacing because of recent claims that it is the result of a galactic merger with the Sagittarius dwarf spheroidal satellite galaxy.

This image was captured from my home in a Bortle 6 zone with darkness readings of 18.9 magnitudes per square arc seconds and naked eye limiting magnitude of 5.5. The sky was clear but seeing was not that great. The humidity was about 80% during the 2.5 hours needed to capture the LRGB frames. There was no wind.