NGC 4490 is a barred spiral galaxy in Canes Venatici around 25 million light-years away, currently in the midst of a close interaction with its smaller companion NGC 4485 — visible just to the north. The gravitational tug-of-war between the two has dramatically distorted NGC 4490, triggering intense starburst activity throughout the disc and producing a luminous, irregular silhouette that gives rise to its popular nickname. The interaction has also drawn out a faint tidal bridge of stars and gas connecting the two galaxies, detectable in deep exposures. NGC 4490 is one of the brightest irregular galaxies in the northern sky and a textbook example of a merger in progress.