NGC 2244

Other image sizes:

3064 x 2039 pixels (full res color)

1600 x 1067 pixels (ha only)

MONOCEROS - EMISSION NEBULA - MAGNITUDE 4.8

THE ROSETTE NEBULA IN MONOCER0S
NGC 2244 - EMISSION NEBULA PLUS CLUSTER

This seems to be a wintertime favorite for most observers and long exposures reveal exactly why. The Rosette, NGC 2244, is a spectacular emission nebula strong in hydrogen gases which lends itself well to filtered exposures that bring out the fainter features. The nebulosity engulfs a few star clusters, NGC 2237, NGC 2238 and NGC 2239. This region is a rich area of dust, stars, and nebulosity due to its position in the winter Milky Way. The cluster is easily viewed with any scope in dark skies. The nebulosity is a bit more difficult to see, however, due to the human eye's inability to see such concentrations of hydrogen-alpha light. Thus, you might need a bit more aperture than you think if you expect to see the Rosette shape itself. If you try it, think big...it's actually a much larger object than you'd think, being over a degree wide, or twice the width of our own moon at full phase.

Full resolution detail of the Rosette dust.

Date: December 17, 2004
Location: The Ballauer Observatory near Azle, Texas
Transparency: 4.8 mag zenithal
Seeing: 7/10
Temperature: 38 degrees F, camera cooled to -25 degrees C
Scope/Mount: Tak FSQ-106 @ f/5 and Tak NJP mount
Camera: SBIG STL-6303E (Ha info) and SBIG STL-11000 (color info), self-guided
Filter: Custom Scientific 4.5nm hydrogen alpha spectral line filter
Exposure Info: Ha (Ha+R) GB, 180:15:40:40 minutes. 15 minutes subexposures (Ha) and 5 minute subexposures RGB); all unbinned.
Processing: Dark frame calibration, flat fields, registration, and Sigma Combine in MaxIm DL 4. Digital Development and RGB combine in MaxIm DL 4. Final HaRGB combine, deblooming, gradient removal, color balance, curves, levels, selective sharpening/blurring/despeckle in Photoshop CS.

THE ROSETTE NEBULA in HYDROGEN-ALPHA LIGHT
USED FOR LUMINANCE IN THE ABOVE COLORED IMAGE

PREVIOUS ATTEMPT:

Location: The Ballauer Observatory near Azle, Texas
Date: February 13, 2004
Temperature: 28 degrees F
Seeing: 7/10 (1.5 FWHM)
Transparency: 5/10
Scope/mount: Takahaski FSQ-106 @ f/5 and Celestron CGE mount
Camera: SBIG ST-10XME, self-guided
Filter: Lumicon 30nm Hydrogen-alpha filter
Exposure Info: Grayscale image - 10 x 10 minute exposures (100 minutes total)
Processing Info: Dark frame calibration, de-blooming, alignment, and Sigma combine in MaxIm 3.0. Digital-development in Images Plus. Curves in Photoshop CS.

Extra information: First light with the ST-10XME and with the new New-Astro Deblooming plug-in. The Lumicon filter is not as narrow as competing versions from Custom Scientific and Astronomiks. Could use extra processing time. Some trailed stars due to some guiding issues with the CGE mount. Special thanks to Dr. Fred Koch for the use of the ST-10.