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arXiv · 2610.08905

KDG 162: A Nearby Isolated Star-forming Dwarf Galaxy

Gagandeep S. Anand·Igor D. Karachentsev·Meredith J. Durbin·R. Brent Tully·Rachael Beaton·Andrew Dolphin·Serafim S. Kaisin·Lidia N. Makarova·Edward J. Shaya
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Abstract

The nearby dwarf galaxy KDG 162 (also known as KK 153) has recently attracted attention as a potentially gas-rich, isolated, and low-mass dwarf galaxy. However, many of these characterizations depend on the true distance to KDG 162. Here we present new Hubble Space Telescope (HST) imaging that resolves individual stars down to 3 magnitudes below the tip of the red giant branch. Using this HST imaging, we determine a distance to KDG 162 of D = 3.48 $\pm$ 0.12 Mpc, somewhat higher than previous determinations. We find KDG 162 to be relatively isolated and lying at the edge of first infall onto the M81 group. We use its stellar content to measure its recent star formation history and find that only a modest amount of star formation can be attributed to within the last $\sim$500 Myr. The present-day stellar mass outweighs the H I mass by a factor of 2$\times$. The properties of KDG 162 add to an increasingly detailed picture of nearby and isolated low-mass galaxies. In the future, deeper observations would allow for reaching more age-sensitive populations, enabling the recovery of its star-formation history back to ancient times.

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Gagandeep S. Anand, Igor D. Karachentsev, Meredith J. Durbin, R. Brent Tully, Rachael Beaton, Andrew Dolphin, Serafim S. Kaisin, Lidia N. Makarova, Edward J. Shaya. 2026-10-06. KDG 162: A Nearby Isolated Star-forming Dwarf Galaxy. https://arxiv.org/abs/2610.08905

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