The Binary Galaxies NGC 147 And NGC 185

Abstract

Contrary to a previously published claim it is found that the spheroidal galaxies NGC 147 and NGC 185 probably form a stable binary system. Distance estimates place this pair on the near side of the Andromeda subgroup of the Local Group. The fact that this system has probably remained stable over a Hubble time suggests that it does not have a plunging orbit that brings it very close to M 31. It is noted that the only two Local Group galaxy pairs, in which the components have comparable masses, also have similar morphological types. NGC 147 and NGC 185 are both spheroidals, while the LMC and SMC are both irregulars. This suggests that protogalaxies of similar mass that are spawned in similar environments evolve into objects having similar morphologies.

To be published in A.J. October 1998

References in corpus (2)

• A new analysis of the Red Giant Branch "Tip" distance scale and the value of the Hubble constant
• Kinematics of the Hercules Supercluster

Cited by in corpus (26)

• The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations
• The M31 Velocity Vector. II. Radial Orbit Towards the Milky Way and Implied Local Group Mass
• The large-scale structure of the halo of the Andromeda galaxy II. Hierarchical structure in the Pan-Andromeda Archaeological Survey
• The Mass of the Andromeda Galaxy
• The satellite distribution of M31
• Local Group Dwarf Elliptical Galaxies: II. Stellar Kinematics to Large Radii in NGC 147 and NGC 185
• The Hubble Space Telescope Survey of M31 Satellite Galaxies I. RR Lyrae-based Distances and Refined 3D Geometric Structure
• Evolutionary Histories of Dwarf Galaxies in the Local Group
• HST Proper Motions of NGC 147 and NGC 185: Orbital Histories and Test of Dynamically Coherent Andromeda Satellite Plane
• The internal dynamics of the Local Group dwarf elliptical galaxies NGC147, NGC185, and NGC205
• A PAndAS view of M31 dwarf elliptical satellites: NGC147 and NGC185
• Long period variable stars in NGC 147 and NGC 185. I. Their star formation histories
• HST/ACS Direct Ages of the Dwarf Elliptical Galaxies NGC 147 and NGC 185
• Newly-Discovered Globular Clusters in NGC 147 and NGC 185 from PAndAS
• Galaxy Pairs in the Local Group
• Blood ties: the real nature of the LMC binary globular clusters NGC 2136 and NGC 2137
• Long-period variables in NGC147 and NGC185
• Globular cluster content and evolutionary history of NGC147
• Herschel and JCMT observations of the early-type dwarf galaxy NGC 205
• Satellite group infall into the Milky Way: exploring the Crater-Leo case with new HST proper motions
• Binary Satellite Galaxies
• NGC 147, NGC 185 and CassII: a genetic approach to orbital properties, star formation and tidal debris
• Astrophysics in 2005
• Correlating the escape dynamics and the role of the normally hyperbolic invariant manifolds in a binary system of dwarf spheroidal galaxies
• The interstellar medium in Andromeda's dwarf spheroidal galaxies: II. Multi-phase gas content and ISM conditions
• A Primeval Magellanic Stream and Others