This incredible image, taken with the Advanced Camera for Surveys (ACS) on board the NASA/ESA Hubble Space Telescope, shows the giant elliptical galaxy NGC 4889.
This image shows NGC 4889 (largest object) in front of hundreds of background galaxies. Image credit: NASA / ESA.
NGC 4889, the brightest and largest galaxy in the image above, is a massive elliptical galaxy located in the Coma Cluster, approximately 341.5 million light-years away.
It was discovered in 1785 by the British astronomer and composer of German origin Frederick William Herschel.
According to astronomers, the galaxy harbors a secret in its center – one of the most massive black holes ever discovered.
This monstrous black hole has about 21 billion solar masses and its event horizon has a diameter of approximately 80.8 billion miles (130 billion km – roughly 15 times the diameter of Neptune’s orbit from the Sun).
Scientists believe that the black hole has stopped feeding, and is currently resting after feasting on NGC 4889’s cosmic cuisine.
The environment within the galaxy is now so peaceful that stars are forming from its remaining gas and orbiting undisturbed around the black hole.
When it was active, NGC 4889’s supermassive black hole was fuelled by the process of hot accretion.
When galactic material – such as gas, dust and other debris – slowly fell inwards towards the black hole, it accumulated and formed an accretion disc.
Orbiting the black hole, this disc of material was accelerated by the black hole’s immense gravitational pull and heated to millions of degrees.
This heated material also expelled gigantic and very energetic jets.
During its active period, astronomers would have classified NGC 4889 as a quasar and the disc around the supermassive black hole would have emitted up to a thousand times the energy output of the Milky Way.
The accretion disc sustained the supermassive black hole’s appetite until the nearby supply of galactic material was exhausted.
Now, napping quietly as it waits for its next celestial snack, the black hole is dormant.
However its existence allows astronomers to further their knowledge of how and where quasars, these still mysterious and elusive objects, formed in the early days of the Universe.
This image of NGC 4889 includes optical and infrared observations from Hubble’s Advanced Camera for Surveys.
