NGC 4372 is an intriguing globular cluster situated in the southern constellation of Musca within our Milky Way galaxy. Its detection was first reported by the notable Scottish astronomer James Dunlop in 1826, and later, in 1834, it was observed by John Herschel.

In a recent study, Kharchenko et al. (2013) presented an exhaustive and sophisticated analysis of the intricate structure and complex kinematics of the ancient, metal-deficient globular cluster NGC 4372. To achieve this, the researchers employed a rigorous methodology involving deep V- and I-band images from archival sources to obtain a color-magnitude diagram (CMD) of the cluster while also correcting for reddening. The resulting data was then used to determine essential parameters, such as the centroid of the cluster, its half-light radius, ellipticity, and foreground stellar density, and the creation of a detailed number density profile. The researchers also utilized state-of-the-art high-resolution spectroscopic techniques to extract the kinematic properties of NGC 4372. They uncovered a significant internal rotation with a maximum amplitude of Arot = 1.2 ± 0.25 km s−1. Furthermore, the best-fit velocity dispersion profile showed a central velocity dispersion of σ0 = 4.56 ± 0.3 km s−1, with the resulting Arot/σ0 ratio of 0.26 ± 0.07 being remarkably high considering NGC 4372’s low metallicity and age. In constructing a realistic dynamical interpretation of NGC 4372, the researchers determined the total dynamical mass of the cluster to be ∼2 × 105 M, with a mass-to-light ratio M/LV ranging from 1.4 to 2.3 M/L. The study also delves into the critical role of internal rotation in shaping the morphology and chemical composition of NGC 4372 while comparing its findings to similar studies of other globular clusters. This scholarly investigation presents an exhaustive and sophisticated analysis of the intricate structure and complex kinematics of the ancient, metal-deficient globular cluster NGC 4372. To achieve this, the researchers employed a rigorous methodology involving deep V- and I-band images from archival sources to obtain a color-magnitude diagram (CMD) of the cluster while also correcting for reddening. The resulting data was then used to determine essential parameters, such as the centroid of the cluster, its half-light radius, ellipticity, and foreground stellar density, and the creation of a detailed number density profile. The researchers also utilized state-of-the-art high-resolution spectroscopic techniques to extract the kinematic properties of NGC 4372 and uncovered a significant internal rotation with a maximum amplitude of Arot = 1.2 ± 0.25 km s−1. Furthermore, the best-fit velocity dispersion profile showed a central velocity dispersion of σ0 = 4.56 ± 0.3 km s−1, with the resulting Arot/σ0 ratio of 0.26 ± 0.07 being remarkably high considering NGC 4372’s low metallicity and age. In constructing a realistic dynamical interpretation of NGC 4372, the researchers determined the total dynamical mass of the cluster to be ∼2 × 105 M, with a mass-to-light ratio M/LV ranging from 1.4 to 2.3 M/L. The study also delves into the critical role of internal rotation in shaping the morphology and chemical composition of NGC 4372 while comparing its findings to similar studies of other globular clusters.

In order to study NGC 4372 and investigate the relationships between the colors, brightnesses, and the age and chemical composition of the cluster as a whole, I collected 5 images in B,  R, and V filters with PROMPT-MO-1, Prompt2, Prompt5 telescopes, with total exposure durations of 110.98 seconds in B, 74.39 seconds in V and 74.39 in R filters, with other imaging parameters, using Skynet (link in reference). I used Afterglow and Cluster Pro Plus for their purposes. And I found these basic results about distance, proper motion, metalicity, etc. The parameters for NGC 4372 Cluster Pro Plus Graph include a distance of 5.807 kiloparsecs, a maximum error of 0.05 magnitudes, a logarithmic age of 10.1 years, a metallicity of -1.945 solar units, and a reddening of 0.389 magnitudes in the B-V color index.

The stacked images with each filter are presented below.

Filter: B, Exposure: 110.98

Filter: R, Exposure: 74.39

Filter: V, Exposure: 74.39

By combining these 3 filters, I made a composite color photo. After that, I used the extension E(B-V) value of 0.389 to calibrate the picture. The photos are shown below.

           NGC4372 composite photo

       NGC4372 calibrated composite photo

The Cluster Pro Plus results are:

The parameters for the plotted graph are:

To conclude, this project was one of the best experiences of my life. I got to go in-depth into a scientific field that has amused me since my early childhood. Being a fan of Carl Sagan, Brain Cox, Brain Green, and many other TV personalities that introduced me to Space, and made me a fan, this project and in a broader sense, this course felt like a nostalgia trip. I have learned a lot and I am very excited to use the knowledge I gained from here in my future endeavor in Cosmology!

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