A stunning new image from the Gemini South telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, shows NGC 7727 — the billion-year-old aftermath of a spiral galaxy collision.
This image from the Gemini South telescope shows NGC 7727, a spiral galaxy located approximately 69 million light-years away in the constellation of Aquarius. Image credit: International Gemini Observatory / NOIRLab / NSF / AURA / T.A. Rector, University of Alaska Anchorage & NSF’s NOIRLab / J. Miller, International Gemini Observatory & NSF’s NOIRLab / M. Rodriguez, International Gemini Observatory & NSF’s NOIRLab / M. Zamani, NSF’s NOIRLab.
NGC 7727 is a spiral galaxy some 69 million light-years away in the constellation of Aquarius.
First discovered by the German-born British astronomer William Herschel on November 27, 1785, the galaxy has a diameter of 115,000 light-years.
Otherwise known as Arp 222 or LEDA 72060, it is the brightest member of the NGC 7727 group (LGG 480).
Astronomers think that NGC 7727 is the product of the merger of two smaller spiral galaxies that took place around one billion years ago.
“The new Gemini South image reveals vast swirling bands of interstellar dust and gas resembling freshly-spun cotton candy as they wrap around the merging cores of the progenitor galaxies,” NOIRLab astronomers said in a statement.
“From the aftermath has emerged a scattered mix of active starburst regions and sedentary dust lanes encircling the system.”
“What is most noteworthy about NGC 7727 is undoubtedly its twin galactic nucleus, each of which houses a supermassive black hole.”
“Stars and nebulae spilled out and were pulled back together at the mercy of the black holes’ gravitational tug-of-war until the irregular tangled knots we see here were created,” they said.
“The two supermassive black holes, one measuring 154 million solar masses and the other 6.3 million solar masses, are approximately 1,600 light-years apart.”
“It is estimated that the two will eventually merge into one in about 250 million years to form an even more massive black hole while dispersing violent ripples of gravitational waves across spacetime.”
“Because NGC 7727 is still reeling from the impact, most of the tendrils we see are ablaze with bright young stars and active stellar nurseries.”
“In fact, about 23 objects found in this system are considered candidates for young globular clusters.”
“These collections of stars often form in areas where star formation is higher than usual and are especially common in interacting galaxies as we see here.”
“Once the dust has settled, NGC 7727 is predicted to eventually become an elliptical galaxy composed of older stars and very little star formation.”
“Similar to Messier 87, an elliptical galaxy with a supermassive black hole at its heart, this may be the fate of the Milky Way and the Andromeda Galaxy when they fuse together in billions of years’ time.”
