NGC 2925 is a relatively young cluster located in the constellation of Vela in the southern hemisphere. NGC 2925’s distance from us is about 2500 light years, which is around 775 parcsecs! This cluster was not discovered by a specific individual, but rather cataloged as part of astronomical surveys. There is not much information on the internet of the specific individuals, or on the group itself, on why and how they discovered this cluster. 

There has not been any real studies on this cluster since it was discovered. This makes it even more interesting, because we do not have that much information in the first place. More extensive research is needed for this cluster, and the information I have gathered over the next few will help us learn a bit more about this mysterious cluster. 

In order to study X and investigate the relationships between the colors, brightness’s, and the age and chemical composition of the cluster as a whole, I collected 15 images (five with the B filter, five with the V filter and five with the R filter). I used a 61 second exposure rate for the B filter, a 31 second exposure rate for the V filter and a 17 second exposure rate for the R filter. I did all of this using Skynet’s robotic telescopes, which captured some beautiful pictures of this star cluster. I used Skynet’s Afterglow and Cluster Astromancer afterwards, to get an estimated color image of the cluster, and to create a and estimate a (RP) – (BP-RP) isochrone model.

These are the basic results that I found with the help of Skynet’s Cluster Astromancer. When estimating the isochrone Figure 1.0 above, I estimated these values: distance: 2.79, log age: 6.6, metallicity: -1.1, e(b-v): 0.46. With these values in the Figure 1.0, it creates an isochrone line that follows through the plotted points, which give me a general sense on what these values could be. 

What do each of these values represent? Well, the distance modulus is a measure of the distance to the star cluster. The log age refers to the logarithm (base 10) of the age of the star cluster in years. A log age of 6.6 means that the age of the star cluster is 10^6.6 years This value gives an estimate of how old the star cluster is. Metallicity indicates the abundance of elements heavier than helium in the star cluster. A metallicity of -1.1 means that the cluster has a metal abundance about 0.1 times that of the Sun. e(b-v) represents the color excess due to interstellar reddening, caused by dust grains in the interstellar medium scattering and absorbing light. A value of 0.46 for E(B-V) indicates a significant amount of reddening.

There are a few other basic things I discovered about this cluster, such as the pm ra = -4.37, the pm dec = 3.51 and the star count being around 2700.

Why study a globular cluster? What did I learn from this experience? Studying a cluster not only helps you understand what is going on in that cluster, but it can also help us understand what is happening outside of that cluster. It can help us understand more about the universe. By analyzing the composition and distribution of stars within a globular cluster, we can infer its age, mass, structure and many other things that are really interesting. My analysis was very interesting because the cluster that I chose has a funky isochrone model. There seems to be some sort of pattern down and to the left that I couldn’t get the isochrone line to follow. There are many things that could affect this, but I believe it is because my photos were not 100% accurate. There also seem to be 1 or 2 giants in the top right, and possibly even some blue stragglers in the bottom left, but there is no nebula. 

According to some data found on HEASARC Browse, they found that the log age was 7.805 and distance was 0.77. When I plug in these data points in my isochrone model I get Figure 1.2. As you can see, they are a bit different but overall they are pretty similar. There’s seems to sit a little lower then where I would put it.

 

Having completed my analysis, I am very glad that I chose this cluster as it was challenging and very interesting.