'Giant arc' stretching 3.3 billion light-years across the cosmos shouldn't exist
A newly discovered crescent of galaxies spanning 3.3 billion - is among the largest known structures in the universe and challenges some of astronomers' most basic assumptions about the cosmos.
The epic arrangement, called the Giant Arc, consists of galaxies, galactic clusters, and lots of gas and dust. It is located 9.2 billion light-years away and stretches across roughly a 15th of the observable universe.
Its discovery was "serendipitous," Alexia Lopez, a doctoral candidate in cosmology at the University of Central Lancashire (UCLan) in the U.K., told Live Science. Lopez was assembling maps of objects in the night sky using the light from about 120,000 — distant bright cores of galaxies where supermassive are consuming material and spewing out energy.
Related content: Cosmic record holders: The 12 biggest objects in the universe
As this light passes through matter between us and the quasars, it is absorbed by different elements, leaving telltale traces that can give researchers important information. In particular, Lopez used marks left by to determine the distance to the intervening gas and dust, as well as the material’s …
More on: www.livescience.com