Giant radio galaxy spanning 16 mn light years across named 'the biggest one' ever found

In a massive discovery, astronomers have found the biggest galaxy ever located about 3 billion light-years away from Earth. Dubbed Alcyoneus, the galaxy is a giant radio galaxy and spans across a whopping 16.3 million light-years and has a supermassive black hole at its center which is around 400 million times the mass of the Sun. While radio galaxies are considered a mystery in the already mysterious universe, astronomers believe that this discovery can provide more clues about such galaxies as well as different mediums drifting in outer space. 

What are radio galaxies?

As the name suggests, radio galaxies are basically the galaxies that emit a high rate of radio waves. Such galaxies are said to consist of a host galaxy, which has a supermassive black hole at its galactic center with star clusters orbiting it. A radio galaxy also has jets and lobes erupting from the center and it is these jets and lobes that generates radio waves while interacting with a galactic medium. These jets in turn are produced by the supermassive black hole sitting at the center of the radio galaxy. The image above shows the lobes of the Alcyoneus galaxy captured by a telescope. 

More about the galaxy and its discovery

The Alcyoneus galaxy was discovered using data from the Europe-based LOw Frequency ARray (LOFAR), which is a network of around 20,000 radio antennas located in 52 locations across the continent, and NASA's Wide-field Infrared Survey Explorer space telescope. The astronomers, who have published their research in the journal Astronomy & Astrophysics, noted that the galaxy is a normal elliptical galaxy but is around 240 billion times more massive than the Sun. According to the study, these parameters have the potential to provide more insights into what is driving the growth of radio wave-producing lobes. 

The astronomers believe that the galaxy is growing bigger, the reason for which is being attributed to a region with density lower than average it is sitting in. "Beyond geometry, Alcyoneus and its host are suspiciously ordinary: the total low-frequency luminosity density, stellar mass and supermassive black hole mass are all lower than, though similar to, those of the medial giant radio galaxies," the researchers write in their paper as per Science Alert.