James Webb Space Telescope Captures Stunning Image of Dwarf Galaxies

A new image from the James Webb Space Telescope captures dwarf galaxies NGC 4490 on the left and NGC 4485 glowing at the upper right, connected by a glowing bridge of gas and dust dotted with bright blue star-forming regions.

This spectacular new view reveals a cosmic collision between the two dwarf galaxies, situated 24 million light-years away, showcasing a gravitational tug-of-war that is reshaping both galaxies. The larger galaxy, NGC 4490, sprawls across the frame, while its smaller companion, NGC 4485, glows off to the upper right.

The bright bridge of gas and dust between them is embedded with clusters of newborn stars, and this interaction has spurred a significant burst of new star formation. According to a statement from the European Space Agency, dwarf galaxies resemble the low-mass, gas-rich, metal-poor systems that populated the early universe, making their collisions and gas exchanges vital for understanding the formation and evolution of the first galaxies.

The galactic pair, collectively called Arp 269, has been previously studied with observations from the Hubble Space Telescope, but Webb's infrared vision has revealed the system in unprecedented detail.

Using Webb's Near-Infrared Camera and Mid-Infrared Instrument, scientists now have an up-close view of individual stars and the fine structure of the gas flowing between the galaxies. By analyzing these galaxies star by star, researchers have mapped where young, middle-aged, and old stars reside, tracing the timeline of their interaction.

Their analysis suggests that the dwarf galaxies swept past each other about 200 million years ago, with NGC 4490 siphoning gas from NGC 4485, creating the visible bridge of exchanged material and fueling waves of star formation, some of which began as recently as 30 million years ago.

This finding underscores the capabilities of the James Webb Space Telescope in observing intricate cosmic phenomena.