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arXiv · 1503.05599

Two Planes of Satellites in the Centaurus A Group

R. Brent Tully·Noam I. Libeskind·Igor D. Karachentsev·Valentina E. Karachentseva·Luca Rizzi·Edward J. Shaya
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Abstract

Tip of the red giant branch measurements based on Hubble Space Telescope and ground-based imaging have resulted in accurate distances to 29 galaxies in the nearby Centaurus A Group. All but two of the 29 galaxies lie in either of two thin planes roughly parallel with the supergalactic equator. The planes are only slightly tilted from the line-of-sight, leaving little ambiguity regarding the morphology of the structure. The planes have characteristic r.m.s. long axis dimensions of ~300 kpc and short axis dimensions of ~60 kpc, hence axial ratios ~0.2, and are separated in the short axis direction by 303 kpc.

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R. Brent Tully, Noam I. Libeskind, Igor D. Karachentsev, Valentina E. Karachentseva, Luca Rizzi, Edward J. Shaya. 2015-03-18. Two Planes of Satellites in the Centaurus A Group. https://doi.org/10.1088/2041-8205/802/2/l25

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