Astronomers have discovered a large quasar group, more commonly referred to as an LQG, that is reported to be the largest known structure in the universe. The discovery was reported in the Monthly Notices of the Royal Astronomical Society journal, and was led by the University of Central Lancashire. The LQG is so large, in fact, that it challenges the Cosmological Principle.
The Cosmological Principle states that when the universe is observed at a large enough scale, it will look the same regardless of where it is being observed from. This principle is based on an assumption, which is now being challenged by the LQG. Just how large is it? According to the Royal Astronomical Society, it would take a car 4 billion years to travel across it at the speed of light.
According to the modern theory of cosmology, a structure like this should not be discoverable at over 370 Megaparsecs, with LQGs being capable of exceeding 200 Mpc. The large LQG discovery, however, measures in at 500 Mpc, with its longest dimension clocking in at 1,200 Mpc. According to RAS, this is about 1,600 times bigger than the distance between Andromeda and the Milky Way.
Dr. Roger Clowes, who led the team that made the discovery, had this to say. "While it is difficult to fathom the scale of this LQG, we can say quite definitely it is the largest structure ever seen in the entire universe. This is hugely exciting – not least because it runs counter to our current understanding of the scale of the universe."