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Leo Trio

A mere 30 million light-years away, large spiral galaxy NGC 3628 (lower right) shares its neighborhood in the local Universe with two other large spirals, in a magnificent grouping otherwise known as the Leo Triplett. In fact, fellow trio member M65 is near the left edge of this deep cosmic group portrait, with M66, just above it and to the right. But, perhaps most intriguing is the spectacular tail stretching up and to the right for about 300,000 light-years from NGC 3628's warped, edge-on disk. Know as a tidal tail, the structure has been drawn out of the galaxy by gravitational tides during brief but violent past interactions with its large neighbors. Not often imaged so distinctly, the tidal tail is composed of young bluish star clusters and star-forming regions.

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