PhotographerKjell H. Winnem
Location of photoHof,Norway
Date/Time of photoMarch 3&7 2010
EquipmentHomebuilt 10 inch Newtonian and mount in dome.
Cam.:Meade DSI Pro II guided off-axis with modified ToUcam 840K Pro II and PHD,GPUSB interface to mount.
Exp.:H-a 3x60min, SII 60min, OIII 60min, CFHT-palette.
Processing:Nebulosity2 and PS CS3.
DescriptionThe Medusa Nebula is a very old and large planetary in Gemini,also known as Abell 21. As it is so big,its surface brightness is very low,with surface magnitudes of between +16 and +25 reported. The Medusa was discovered i 1955, and until the early 1980s it was thought to be a supernova remnant.