December 5, 2012
New One Degree Imager Camera Captures Stunning Image Of The Bubble Nebula
April Flowers for redOrbit.com - Your Universe Online
A spectacular new image of the Bubble Nebula, named NGC 7635, has been captured by the new camera known as the One Degree Imager (ODI) that is being commissioned at the WIYN 3.5-meter telescope at the Kitt Peak National Observatory outside Tucson, Arizona.
Located in the constellation Cassiopeia, the Bubble Nebula is approximately 10 light-years across. It is a shell of gas and dust carved out by stellar wind created by the massive central star BD+60 2522. The nebula is ionized by the same star's high-energy light.
ODI's wide field view of the Bubble Nebula covers an area of the sky of 25 by 25 arc minutes, which is just a little smaller than the full moon. The sharpness of the stars to the right edge of the image, rendered in exquisite resolution, is a hint of things to come with ODI.
The image was created using three different filters, called g, r, and i, which were then assigned to the colors blue (g), red (r) and yellow (i). Although the wide field image has not been fully corrected to remove all defects and artifacts from the data reduction process, the smaller accompanying image is a work of art as well as science.
Dr. Travis Rector, an astronomer with the University of Alaska Anchorage who did the work on the smaller image, explains, “When making an image in effect we are translating what the telescope can see into something our eyes can see. In the process of generating an image, we assign different colors to each filter that we use. Where possible we assign colors to each filter that roughly corresponds to what the human eye would see.”
The data reduction process is a very complex multistage operation, even before color combining. The Science Data Management group at the National Optical Astronomy Observatory (NOAO) first processes the ODI data, which is then moved to and archived at Indiana University's Pervasive Technology Institute, using an NSF supercomputing facility.
There are issues that need to be addressed, including the sheer number of pixels in the multiple CCDs. Right now, ODI is operating with only 13 of the total 63 CCDs. When the camera is fully functional, it will be able to image an area of the sky five times that of the full moon. This is far larger than any previous camera at the WIYN telescope. ODI will be able to resolve objects to better than 0.4 arc seconds because of its sensitivity to visible light.
Funding for the ODI camera is provided by the WIYN partners (University of Wisconsin, Indiana University, Yale University, and the National Optical Astronomy Observatory), and the National Science Foundation, through its Telescope System Instrumentation Program.
Visit Dr. Rector's site to learn more about how these images are created.