Owl Nebula (M97)

clic for 50% size 1128 x 962 (118 kB)


About this Image

The faint Owl Nebula M97 is one of the more complex planetary nebulae. Its appearance has been interpreted as that of a cylindrical torus shell (or globe without poles), viewed oblique, so that the projected matter-poor ends of the cylinder correspond to the owl's eyes. This shell is enveloped by a fainter nebula of lower ionization. The mass of the nebula has been estimated to amount 0.15 solar masses, while the 16 mag central star is believed to be of about 0.7 solar masses. Its dynamical age is about 6,000 years. Its distance is uncertain; ranging from 1,300 up to 10,000 light years. In the background around this nebula there are several small nebulous objects, very distant galaxies, the brightest one near the brighter star left of M97, mag 16 PGC34279. North is up-right.

Below you see a crop on the center of the above image in 40/80% size.

clic for 80% size 924 x 790 (60 kB)


Technical Details


16" cassegrain in secondary focus at f/10

Mount MK-100 GEM
Camera SBIG STL-11000M at -20C, internal filter wheel
Filters Astronomik LRGB
Date Apr 14, 2005.
Location Wildon/Austria
Sky Conditions mag 5 sky, Moon up, raw FWHM 1.6-1.8", temperature 10 C
Exposure L:R:G:B = 40:30:30:30 minutes (10-minute sub-exposures),
Processing Image aquisition in Maxim, image calibration, aligning, DDP in ImagesPlus; color balance, curves, unsharp mask in Photoshop; Noise reduction by Neatimage;