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A new galaxy near the Local Group in Draco

I. D. Karachentsev·M. E. Sharina·A. E. Dolphin·D. Geisler·E. K. Grebel·P. Guhathakurta·P. W. Hodge·V. E. Karachentseva·A. Sarajedini·P. Seitzer
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Abstract

We present HST WFPC2 and ground-based images of the low surface brightness dwarf Irr/Sph galaxy KKR~25 in Draco. Its colour-magnitude diagram shows red giant branch stars with the tip at I = 22.32 mag, and the presence of some blue stars. The derived true distance modulus, 26.35 \+- 0.14 mag, corresponds to linear distances of KKR25 from the Milky Way and from the Local Group centroid of 1.86 and 1.79 Mpc, respectively. The absolute magnitude of the galaxy, M_V = -10.48, its linear diameter (0.54 Kpc) and central surface brightness (24.0 +- 0.2 mag\arcsec^2) are typical of other dIrr/dSphs in the Local Group. Being situated just beyond the radius of the zero-velocity surface of the Local Group, KKR25 moves away from the LG centroid at a velocity of V_{LG} = + 72 km/s.

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I. D. Karachentsev, M. E. Sharina, A. E. Dolphin, D. Geisler, E. K. Grebel, P. Guhathakurta, P. W. Hodge, V. E. Karachentseva, A. Sarajedini, P. Seitzer. 2001-10-06. A new galaxy near the Local Group in Draco. https://doi.org/10.1051/0004-6361%3A20011344

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