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The nature of the new Local Group Galaxy Antlia

A. Aparicio·J. J. Dalcanton·C. Gallart·D. Martinez-Delgado
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Abstract

The recently discovered Antlia dwarf galaxy in analyzed using VI photometry. The galaxy is resolved into a large number of stars and although the galaxy is intrinsically faint and low surface brightness, its stellar populations reveal characteristics more typical of faint star-forming dIrs rather than dEs. Significant star formation is currently going on in the central part of Antlia, although little or no star formation is taking place in the outer regions. The distance of Antlia is 1.32 Mpc. It is a close companion of the larger dIr NGC 3109, although gravitational bounding between both galaxies is not clear. The SFR is estimated for the last 1 Gyr and for the entire galaxy life. The mass locked into stars and stellar remnants, the gas mass and the total mass are estimated.

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A. Aparicio, J. J. Dalcanton, C. Gallart, D. Martinez-Delgado. 1997-06-19. The nature of the new Local Group Galaxy Antlia. https://arxiv.org/abs/astro-ph/9706197

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