International Journal of Astronomy and Astrophysics, 2020, 10, 1-10 https://www.scirp.org/journal/ijaa ISSN Online: 2161-4725 ISSN Print: 2161-4717 DOI: 10.4236/ijaa.2020.101001 Feb. 6, 2020 1 International Journal of Astronomy and Astrophysics Virgo Cluster Membership Based on K-Means Algorithm Ibrahim Mohamed Selim 1,2 , Passent Elkafrawy 3 , Walid Dabour 3,4 , Mohamed Eassa 2 1 National Research Institute of Astronomy and Geophysics, Cairo, Egypt 2 Computer Science Department, Integrated Thebes Institute, Cairo, Egypt 3 Math and Computer Science Department, Faculty of Science, Menoufia University, Shibin El Kom, Egypt 4 Computer Science Department, Taibah University, Alula Branch, Medina, KSA Abstract The Virgo cluster of galaxies is of great importance to study the development of the universe due to its close distance from the earth as well as being the center of the local super cluster. The problem that faces Virgo cluster studies is that it shares the same right ascension (RA) and Declination (DEC) ranges with large number of background as well as foreground galaxies. This study aims to geometrically and statistically estimate Virgo cluster membership. The study employs Virgo cluster data, prepared by Harvard University. The radial velocity (RV) data of the Virgo cluster were treated and employed in exchange of missing galaxies’ third dimension, taking advantage of their proportionality. The data were treated by K-means algorithm, using Matlab 2014, and visual and logical exclusion of extremity galaxies to determine the rational center of the Virgo galaxies cluster. Results were presented, com- pared and discussed. Finally distances of galaxies from the Virgo cluster cen- ter were employed along with normal probability distribution characteristics to identify the most probable Virgo cluster members from the range of Virgo cluster of galaxies. The results showed that out of 17,466 objects surveyed in Virgo galaxy range, only few of galaxies were estimated to be genuine Virgo members. Keywords Virgo Cluster, K-Means, Normal Distribution 1. Introduction The study of the Virgo cluster is important to explore the development stages of the universe. This cluster is the nearest large high-density cluster to earth, at How to cite this paper: Selim, I.M., Elka- frawy, P., Dabour, W. and Eassa, M. (2020) Virgo Cluster Membership Based on K-Means Algorithm. International Journal of Astronomy and Astrophysics, 10, 1-10. https://doi.org/10.4236/ijaa.2020.101001 Received: July 12, 2019 Accepted: February 3, 2020 Published: February 6, 2020 Copyright © 2020 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access