Studying the contribution of components and type of spiral galaxy NGC 6946 using digital image processing

A K Ahmed

doi:10.30723/ijp.v13i28.240

Abstract

NGC 6946 have been observed with BVRI filters, on October 15-18,2012, with the Newtonian focus of the 1.88m telescope, Kottamiaobservatory, of the National Research Institute of Astronomy andGeophysics, Egypt (NRIAG), then we combine the BVRI filters toobtain an astronomical image to the spiral galaxy NGC 6946 whichis regarded main source of information to discover the components ofthis galaxy, where galaxies are considered the essential element ofthe universe. To know the components of NGC 6946, we studied itwith the Variable Precision Rough Sets technique to determine thecontribution of the Bulge, disk, and arms of NGC 6946 according todifferent color in the image. From image we can determined thecontribution for each component and its percentage, then what is thepercentage mean. In this technique a good classified image resultand faster time required to done the classification process.

Highlights

NGC 6946 is a Spiral galaxy with 8.9 mag, was discovered by William Herschel[1] on September 9, 1798
NGC 6946 is a rather nearby spiral galaxy, which at one time was suspected to be an outlying member of the Local Group[2]
Located at a distance of 5.9 Mpc, NGC 6946 is a large spiral galaxy seen almost face-on[3], shows a bright central nucleus, the central regions are affected by dust extinction (Elmegreen et al 1998)[4]

Summary

Introduction

NGC 6946 is a Spiral galaxy with 8.9 mag, was discovered by William Herschel[1] on September 9, 1798. NGC 6946 is a rather nearby spiral galaxy, which at one time was suspected to be an outlying member of the Local Group (see Hubble 1936)[2]. Based on previous facts we will use one of the image processing techniques- Variable Precision Rough Sets- for the study of galactic and the percentage of each component, which contributed to the classification of the galaxy NGC 6946, which is classified by de Vaucouleurs et al 1991[7] as SAB(rs)cd. In which POS(P, Q, β) is a β-position region on part ion Q* Attribute reduction and optimal set of attribute are the most important conception in rough sets model. In the absence of attribute cost function, two basic approaches were presented by Ziarko in which optimal reduction can be determined according to the number of attributes and rules [10]

Experimentanalysis In this workwe was take

Results and discussion

Conclusions