The “Eye of Sauron,” scientifically known as the nearby NGC 4151 galaxy, is helping scientists to determine the distance to other galaxies tens of millions of light-years away, according to a new study.
The research, which is published in the journal Nature,was used to identify the accurate distance of the nearby NGC4151 galaxy, which wasn’t previously available. The galaxy NGC 4151, which is dubbed the ‘Eye of Sauron’ by astronomers for its similarity to the film depiction of the eye of the character in The Lord of the Rings, is important for accurately measuring black hole masses.
A team of scientists, led by Dr Sebastian Hoenig from the University of Southampton, have developed a new way of measuring precise distances to galaxies tens of millions of light years away, using the W. M. Keck Observatory near the summit of Mauna Kea in Hawaii.
“Such distances are key in pinning down the cosmological parameters that characterize our Universe or for accurately measuring black hole masses,” leader Dr. Sebastian Hoenig, from the University of Southampton, said in a statement.
According to the previous calculation, the distance of this galaxy, from Earth, is ranging from 4 to 29 megaparsecs. However, using this new method, researchers can calculate the distance more accurately. This galaxy lays 19 megaparsecs, or nearly 62 million light-years, away from Earth.
To measure the physical size of the dusty ring, the researchers measured the time delay between the emission of light from very close to the black hole and the infrared emission. This delay is the distance the light has to travel (at the speed-of-light) from close to the black hole out to the hot dust.
Dr Hoenig, together with colleagues in Denmark and Japan, is currently setting up a new program to extend their work to many more AGN. The goal is to establish precise distances to a dozen galaxies in this new way and use them to constrain cosmological parameters to within a few per cent. In combination with other measurements, this will provide a better understanding of the history of expansion of our universe.
Sources: Nature World News, National Geographic, Science Daily,