Sept. 28 (UPI) — A new image captured by the Hubble Space Telescope showcases a region of intense star formation inside the galaxy NGC 4490.
The dense region of stellar activity was energized by a collision, a collision inspired by gravity. Though relatively weak, compared to other physical phenomena, the force of gravity has a long reach. It can influence massive cosmic structures across vast distances.
Over millions of years, gravity pulled together NGC 4490 and its smaller neighbor, the irregular galaxy NGC 4485. The two galaxies are no longer colliding, as their momentum has carried them away from each other once more. But the effects of the smashup have significantly altered the pair.
The duo form what astronomers call Arp 269, a system included in the Atlas of Peculiar Galaxies. The collision has warped each galaxy’s shape and altered its contents, blessing each with an influx of fresh star-making material.
The intense ultraviolet radiation given off by young, hot stars cause clouds of hydrogen to become ionized, turning these pockets of intense star formation a bright pink color.
NGC 4490 was once a barred spiral galaxy, similar in appearance to the Milky Way. But the collision stretched out the galaxy’s arms. Its elongated, nebulous shape earned it the nickname the Cocoon Galaxy.
NGC 4490 and NGC 4485 are currently speeding away from one another, but they are connected by a bridge of star formation stretching some 24,000 light-years. Eventually, gravity will pull the pair back together, and another collision will inspire new generations of stars in a few billion years.