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The Stellar Content of NGC 6789, A Blue Compact Dwarf Galaxy in the Local Void

Igor O. Drozdovsky·Regina E. Schulte-Ladbeck·Ulrich Hopp·Mary M. Crone·Laura Greggio
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Abstract

We find that NGC6789 is the most nearby example of a Blue Compact Dwarf galaxy known to date. With the help of WFPC2 aboard the Hubble Space Telescope, we resolve NGC6789 into over 15,000 point sources in the V and I bands. The young stars of NGC6789 are found exclusively near the center of the galaxy. The red giant population identified at large galacticentric radii yields a distance of about 3.6 Mpc, a stellar metallicity [Fe/H] of about -2, and a minimum age of about 1 Gyr. Despite its isolated location in the Local Void,its low metallicity, and its active star formation, the properties of NGC6789 are clearly not those of a galaxy in formation.

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Igor O. Drozdovsky, Regina E. Schulte-Ladbeck, Ulrich Hopp, Mary M. Crone, Laura Greggio. 2001-02-26. The Stellar Content of NGC 6789, A Blue Compact Dwarf Galaxy in the Local Void. https://doi.org/10.1086/320021

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