Introduction
IC 2948, which can also denoted as the Running Chicken Nebula, The lambda Centauri Nebula. This young open star cluster is located in the southeast region of the Centaurus constellation 6 500 light years away from our Earth at a Right Ascencion of 11:39:12.72 and a Declination of -63°30’36.0″. It is also often considered to be associated together with the emission nebula IC 2944, all together, being known to be the brightest emission and reflection nebula among its neighbors in the southeast region of Centaurus.
Figure 1.1: shows lambda Centauri (λ) somewhere at the bottom middle-right of the Centaurus constellation. (exoplanet.nasa.gov, 2022)
Figure 1.2: circles the location of lambda Centauri in its constellation. (theskylive.com, 2023)
First known discovery of this star cluster is through the astronomer A. Dacid Thackeray in the 1950s in his observation of the bok globules found within the star cluster.
Article of discovery can be found in (academic.oup.com, 1965) linked below.
Some say that IC 2948 and/or 2944 got their name, The Running Chicken Nebula either from certain portions of the star cluster’s nebulosity that resembled a bunch of bird-like creatures or from a group of stars within the young cluster which resembled a shape of a running chicken.
Procedure
I was able to photograph a colored image of this open cluster by the use of the prompt 5 telescope located at Cerro Tololo Inter-American Observatory. This telescope has a 0.4m aperture, a 4576.0mm focal length, with a focal ratio of 11.3, a CCD size of 102 um pixels and an 10 x 10 arcmins field of view.
Figure 2.1: Shows telescopes from Cerro Tololo Inter-American Observatory (CTIO), (noirlab.edu, 2020)
On February 24 2023, with the use of this telescope I was able to take about five exposures of each B, V, and R Johnson/Cousins BVRI broadband filters of the star cluster which images I then stacked on top of one another.
Figure 3.1 (left): Is the B filter image, Figure 3.2 (bottom): Is the V filter image, Figure 3.3 (right): Is the R filter image. All images are taken by me using Skynet observation robotic telescope prompt5 (Skynet.unc.edu, 2023)
Before I started coloring the image by changing its color mode, I first estimated the reddening that is happening within the image through the use of the data I have collected from Skynet’s Afterglow photometry feature and plotting system. After fitting my Isochrone model I used those settings in order to determine the amount of reddening that was in the image and continued with the colorization of the black and white images.
Figure 4.1: Shows my fitting of the isochrone model along with the modifications to metallicity, age, distance, in order to get my E(B-V) Reddening, (Skynet.unc.edu, 2023)
With all the procedure, I was able to obtained the finish product of the colorized and dereddened image of the star cluster IC 2948. For some reason my image had this weird miniature streaks on the brighter stars of the image. We are also able to see a piece of bok globule right on top of the bright red nebulous gas. We can also see a great variety of stars with varying temperatures, magnitudes, etc. based off of the color that they display in the image.
Figure 5.1: Shows the finished colorized image along with the dereddening of the IC 2948 star cluster. (Skynet.unc.edu, 2023)
This project was most likely my favorite just because I was able to observe and collect my own images, and was able to get a beautiful finished product after figuring out certain features of the image such as the brightness of the individual stars, how I was able to determine their colors based off of the information about their magnitudes from black and white images, to the fitting of the isochrone model to figuring out how much reddening was happening to the cluster due to the interstellar dust absorbing and scattering the colors of the image.
References
https://astrodrudis.com/ic-2948-the-running-chicken-nebula/
https://en.wikipedia.org/wiki/IC_2944
https://theskylive.com/sky/stars/lambda-centauri-star
https://academic.oup.com/mnras/article/131/1/121/2604187?login=true