Bubble Nebula in mapped color (NGC 7635)

clic for 50% size 1166 x 886 (234 kB)

clic here for 80% size 1863 x 1415 (457 kB)


About this Image

NGC 7635, the Bubble Nebula, a nebula that is being shaped by a young hot star in its center.
The star 40 times more massive than the Sun is blowing a giant bubble of material into space. The dense gas surrounding the star is shaping the castoff material into a bubble. The bubble's surface is not smooth like a soap bubble's. Its rippled appearance is due to encounters with gases of different thickness.
The shell is being shaped by a very strong stellar wind of material and radiation which is emanating from the bright star forming shock waves. 11,300 light-years from us, the Bubble Nebula lies in the constellation Cassiopeia.
The image uses Sulphur-II as red channel, H-alpha as green and Oxygen-III as blue channel, a typical mapped color image using the Hubble palette.
North is to the left.

Checkout the Ha-O3 version in normal color assignment: here.

Check a wider view: here.

Compare a close-up image of the Hubble Space Telescope here.

Checkout a flash animation blending the normal image with the mapped one: here (press F11 for full screen).

Technical Details


16" Cassegrain in secondary focus at f/10

Mount MK-100 GEM
Camera SBIG STL-11000M at -20C, 1x1 bin, internal filter wheel
Filters Baader 7 nm Ha, Astronomik 13 nm O-III and S-II
Date Sep 01-13 2006.
Location Wildon/Austria
Sky Conditions mag 5 sky, seeing 1.3-1.6", temperature 16 C
Exposure S-II:Ha:O-III = 360:210:270 minutes (30-minute sub-exposures)
Processing Image aquisition in Maxim DL; calibration, aligning, stacking in CCDStack;
Photoshop: levels and curves, color balance, H-alpha partly as luminance, unsharp mask, blurring for background