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تسجيل مستخدم جديدDiscovery of a cold stellar stream in the ATLAS DR1 data
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We report the discovery of a narrow stellar stream crossing the constellations of Sculptor and Fornax in the Southern celestial hemisphere. The portion of the stream detected in the Data Release 1 photometry of the ATLAS survey is at least 12 degrees long, while its width is $approx$ 0.25 deg. The Color Magnitude Diagram of this halo sub-structure is consistent with a metal-poor [Fe/H] $lesssim -1.4$ stellar population located at a heliocentric distance of 20 $pm$ 2 kpc. There are three globular clusters that could tentatively be associated with the stream: NGC 7006, NGC 7078 (M15) and Pyxis, but NGC 7006 and 7078 seem to have proper motions incompatible with the stream orbit.
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