This discovery image of a giant, low-surface-brightness, looplike stellar structure around edge-on spiral NGC 4013 was obtained with a 20-inch amateur telescope. The marked redder color of the stream material compared to the outer parts of the disk suggests that this loop did not originate from the disk itself, but rather is the tidal stream of a dwarf galaxy being destroyed by its interaction with NGC 4013.
R. Jay GaBany