Specific IC 2118 information
Contents
The cloud
IC 2118, the Witch Head Nebula is a small cloud near the supergiant star Rigel in the constellation Orion. In the image at the right (taken by IRAS at 25 microns), IC 2118 is the structure at the bottom right corner. Rigel appears to be at least partially responsible for exciting and blowing off a significant portion of the nebula in this region. This cloud is about 210 parsecs away, similar in distance to the Orion Nebula Cluster (a.k.a. the ONC, or the sword of Orion). The ONC is a cluster of stars that are so bright that they too may be pushing around the gas and dust in the Witch Head Nebula.
What we are trying to do is characterize the process of pre-main sequence stellar evolution in this cluster. We want to be able to compare star formation in this cluster with others to see if there are similarities or differences.
Previous all-sky surveys, including both IRAS and 2MASS, have included this region, but not to the resolution or the wavelengths that Spitzer can provide, and there are few studies of this particular region in the literature.
Need to have more information here on a literature review
The observations
will include which regions we observed and when
A first look at the catalog with color-color plots
this discussion will center on using color-color plots with the catalog. Need to emphasize here (and earlier) that many of the tools and techniques developed for IC 2118 will work in any other star-forming region observed with Spitzer.
