Date of Award

Spring 5-2023

Document Type


Degree Name

Master of Science (MS)



Committee Director

Balša Terzić

Committee Member

Alexandre Deur

Committee Member

Alexander Godunov


Recent research has shown a relationship between spiral galaxy satellite populations and the size of spiral bulges. The modern cosmological model of our universe (ΛCDM), does not predict this. Instead, ΛCMD predicts that only the total dynamical mass of a host galaxy should be correlated with satellite populations. We investigate this relationship in regimes other than satellites. In this study we compare the bulge to total mass ratios of spiral galaxies to the number of nearby galaxies within “n” Mpc. We use four papers from literature that calculate bulge to total mass ratios of 189 spiral galaxies using different techniques. We reduce these 189 galaxies down 99 galaxies who all have heliocentric-corrected redshift values 0.005 ≤ z ≤ 0.03. We use NASA Extra-galactic Database (NED hereafter) to determine the number of nearby galaxies within “n” Mpc of each of the selected spirals. We consider the relative luminosity completion in this database as well as the inaccuracies that are inherent in such large scale ”crowd sourced” databases. From these considerations we make appropriate cuts. Finally we compare our results with recent literature and determine the effectiveness of using NED in this way. We find using NED is currently impractical for determining accurate nearby galaxy counts. For this reason, We find no obvious correlations between spiral galaxies bulge to total mass ratios and the number of nearby galaxies within “n” Mpc.


In Copyright. URI: This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).