Object Information:

 

This interesting object is a reflection nebula comprised of gas and dust and is illuminated by the star, R Monocerotis, at the base of the nebula.  The interesting aspect of NGC 2261 is that the appearance of the nebula can change over a period of a few weeks.  One theory of the mechanism of the change in appearance is that dense knots of dust near R Monocerotis casts changing shadows on the reflection nebula.  More information on NGC 2261 can be found at:

 

http://antwrp.gsfc.nasa.gov/apod/ap991020.html

 

and at 

 

http://www.umanitoba.ca/faculties/science/astronomy/cbrown/imaging/hvn/introduction.html

 

A very nice animation of the changes in appearance can be found at:

 

http://www.umanitoba.ca/faculties/science/astronomy/cbrown/imaging/hvn/hvnanimation.html

 

  Imaged at: 

 

Blair Valley, Anza-Borrego Desert State Park, San Diego County, California;
Elevation - 2,200 feet

  Equipment:  

 

Optics - RC Optical Systems 10" Ritchey-Chrétien optical tube at f/9,
Mount - Astro Physics 1200 GTO,
Camera - Santa Barbara Instrument Group (SBIG) ST-10XME NABG CCD,
Filter - SBIG CFW-8 with Astrodon "E" Series CRGB filters

  Exposure Information:

 

January 28, 2006
A sum of five unfiltered 360 second images.

  Camera Control Software:

 

CCD Soft Ver. 5

  Image Processing Software:

 

Image calibration - MIRA AP 7; Final processing - Photoshop CS