A brand new image from the Hubble Space Telescope reveals a galaxy overshadowed by its larger, merging companions.
Positioned roughly 500 million light-years from Earth lies a galactic pair collectively often known as Arp-Madore 2339-661. The 2 galaxies are within the technique of merging, in line with a press release from the European Space Agency. One galaxy is often known as NGC 7733 — the smaller galaxy seen within the lower right — and the opposite is NGC 7734 — the larger galaxy within the upper left.
Nevertheless, hidden within the star-studded spiral arm of NGC 7733 is one more galaxy, known as NGC 7733N. Until now, this realm has seemed to be obscured by dark dust. Using the Hubble data, nonetheless, astronomers were in a position to discern a knot-like structure with a notable red glow, standing out compared to the intense blue stars of NGC 7733.
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“This might easily pass as a part of NGC 7733, but evaluation of the velocities (speed, but additionally considering direction) involved within the galaxy shows that this knot has a substantial additional redshift, meaning that it is vitally likely its own entity and never a part of NGC 7733,” ESA officials said within the statement.
The three galaxies all lie relatively close to one another within the constellation Tucana and are interacting gravitationally with each other. The Hubble photo captures the exchange of fabric between NGC 7733 and NGC 7734, that are on track to merge right into a single, larger galaxy. Because the galaxies grow closer, the gravitational pull of NGC 7734 siphons gas and dirt from its smaller companion.
“This is definitely one in all the various challenges that observational astronomers face: understanding whether an astronomical object really is only one, or one lying in front of one other as seen from Earth’s perspective!” ESA officials said.