NGC 4438
Looking out into the cosmos, the distances to even the nearest galaxies can seem immense, and yet spiral galaxies collide frequently. As two galaxies approach, their gravitational interactions cause them to distort each other.
You can get a sense of what happens when spiral galaxies engage this way if you look into the constellation of Virgo – specifically within Markarian’s Chain. In the chain are two galaxies – known as The Eyes – that lie roughly 50 million lightyears from us. The pair are catalogued as NGC 4438 and NGC 4435, and deep images of NGC 4438 show a contorted jumble of scattered dust lanes and ribbon-like streams of stars around a brighter, central region. Astronomers think that what we’re seeing in NGC 4438 is actually a spiral galaxy that’s been disrupted by a violent encounter with the elliptical galaxy M86, which now sits less than 0.5º away on the sky.