The Hubble Space Telescope unveiled a striking cosmic spectacle: the merger of two spiral galaxies, named UGC 05028 and UGC 05029, collectively known as Arp 300.
Spiral galaxies UGC 05028 and UGC 05029, also known as Arp 300, captured by the Hubble Space Telescope. This image shows the rapid star formation triggered by the interaction between these galaxies.
Credit: NASA/ESA/J. Dalcanton (University of Washington)/R. Windhorst (Arizona State University)/Processing: Gladys Kober (NASA/Catholic University of America)
The gravitational interaction between these two galaxies is a captivating phenomenon. The smaller one, UGC 05028, is heavily influenced by the gravitational field of its larger counterpart, UGC 05029. This gravitational dance has led UGC 05028 to adopt an asymmetrical and irregular structure, invisible from Earth-based telescopes, but distinctly captured by Hubble.
Hubble's images show these galaxies "face-to-face," that is, with their luminous centers and spiral arms clearly visible. This perspective reveals their circular and disc-like shape, unlike a side view where they would appear more oval and flattened. Worth noting, another galaxy viewed from the side is also present in the image, below UGC 05029.
A remarkable feature is the bright knot located southeast of the core of UGC 05028, possibly the result of another ongoing galactic merger. Once this merger is complete, the rest of the galaxy will be absorbed, promoting the formation of a prominent central bulge, similar to that observed in UGC 05029, and stimulating the birth of new stars.
The rapid star formation is particularly evident in UGC 05029. The interaction with UGC 05028 has triggered intense star birth, visible through numerous hot blue giant stars on the spiral arms of UGC 05029.
By studying Arp 300, Hubble helps us better understand the relationship between the physical features of these galaxies and the dynamics of their star formation. Moreover, this observation has captured other objects in the galactic neighborhood, including a grouping of five distant galaxies near the bottom of the image.
These findings underscore the importance of space observation for our understanding of the Universe, offering insight into the dynamic forces that shape galaxies and stimulate the creation of new stars.