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Leo V: A Companion of a Companion of the Milky Way Galaxy

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 نشر من قبل N. W. Evans
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف V. Belokurov




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We report the discovery of a new Milky Way dwarf spheroidal galaxy in the constellation of Leo identified in data from the Sloan Digital Sky Survey. Leo V lies at a distance of about 180 kpc, and is separated by about 3 degrees from another recent discovery, Leo IV. We present follow-up imaging from the Isaac Newton Telescope and spectroscopy from the Hectochelle fiber spectrograph at the Multiple Mirror Telescope. Leo Vs heliocentric velocity is 173.4 km/s, which is offset by about 40 km/s from that of Leo IV. A simple interpretation of the kinematic data is that both objects may lie on the same stream, though the implied orbit is only modestly eccentric (e = 0.2)

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