What makes the Tucana Dwarf distinct from other dwarf galaxies comes in two parts: its classification, and its isolation. As a dwarf spheroidal galaxy, it is much smaller and less luminous than most other dwarf galaxies. Dust is sparse and the stellar population skews towards the older range, giving them a dimmer look. Additionally, the Tucana Dwarf lies about 3.6 million light-years from the Local Group’s center of mass, far from the Milky Way and other galaxies. It is only one of two dwarf spheroidal galaxies in the Local Group to be this remote, making astronomers theorize that a close encounter with a larger galactic neighbor called Andromeda slingshotted it into the distance about 11 billion years ago.
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