Interacting Galaxies

A streak of space dust and gas crosses the enormous gulf between two dwarf galaxies that whirled close together hundreds of millions of years ago, then drifted an incredible distance apart. NGC 4490, the larger of the two (whose diffuse light is seen at the image's left edge), long ago captured a mass of nebular material from its then-neighbor NGC 4485 (seen as a loose star cluster at the upper right). As the galaxies separated, this mass was stretched into an astronomically long trail. The resulting intergalactic bridge is a breeding ground for stars: peppered throughout its span are regions of heavy ionization from new star clusters, blazing neon blue in this near-infrared shot from the James Webb Space Telescope.