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The first draft bar graph above shows no corrrelation between galaxy age and stellar mass. One possible explanation could be that stars do not die within these galaxies in a detectable way (i.e. their energy remains, so galaxies will maintain their distributions of stellar mass across early and late types).
The data in the first draft of this second plot were inaccurately represented and the plot was rather small. On the other hand, the second draft of the second plot (above) is a more accurate example of what the plot would look like if finished. The plot illustrates the relative quantities of elliptical, spiral, and indeterminate-type galaxies. Most galaxies are uncertain-type galaxies, which means most galaxies that can’t be described in terms of an elliptical/spiral binary. There are some explanations for the lack of a pattern. For one, the number of galaxies is in the hundred thousands, which results in difficulties when it comes to their categorization. This plot assumes that the citizen scientists accurately classified galaxy type, including uncertain classifications.
The plot above shows no correlation between galaxy type and stellar mass; stellar mass ranges retain their member frequency across the galaxy types. This is contrary to our hypothesis and may indicate that stellar mass remains constant despite declining star formation in late type galaxies or that, if younger galaxies have more star formation than do older galaxies, galaxy age distribution does not differ across galaxy types. As stellar mass indicates star formation, and star formation indicates galaxy age, the stellar mass distribution we have graphed should correlate to the galaxy age distribution. The above plot indicates that the relative proportions of frequency across stellar mass ranges remain constant from one galaxy type to the next, at least in the stellar mass sample range for our dataset.
The above plot illustrates rather clearly the relative proportions of stellar mass ranges. Very clearly, the plot shows early type, merger, and late type galaxies to be composed, to the same degree, of galaxies within stellar mass ranges. Therefore, it appears as though a relative ratio of stellar mass ranges is present throughout all three galaxy types.
The above plot shows the distribution of stellar mass to remain constant from early type to merger to late type galaxies. While this shows no correlation between galaxy type and distribution of stellar mass (quantity of galaxies within a certain stellar mass range changes only corresponding to an overall increase in galaxies of a certain type), it does reveal something else of intrigue: a constant distribution. The shape of the area plot is a "v"; however, so are each of the sectors of the area plot. To simplify, this shows a proportional relationship between overall quantity of galaxies and the relative quantities of galaxies within each stellar mass range.
Please note that "early type" and "late type" are terms used within our dataset, and plot labels reflect this so as to maintain consistency between the dataset and the graphical representations of it. As they relate to our research questions, "early type" refers to an elliptical galaxy and "late type" refers to a spiral galaxy. Additionally, although present in neither our research questions nor our procedure, "merger" galaxies are represented in some of our plots. This is simply to demonstrate that the pattern of distribution of the quantity of galaxies within a mass range also holds true in a sample of merger galaxies.
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