Seeing Giants

If you heat up some alphabet soup, you shouldn’t end up with all the letters clumped together — they should be fairly evenly spread throughout the pot.

According to the current understanding of the universe, the same thing should apply to galaxies. They may clump together on smaller scales, forming clusters and even super-clusters. But when you look at the universe as a whole, the galaxies ought to be evenly spread. Yet astronomers have found giant galaxy structures that seem to defy that idea — they can span billions of light-years.

Two recently discovered examples are the Big Ring and the Giant Arc. Both of them appear near the Big Dipper. And they may be related.

Both were discovered by a graduate student in England, who used a lot of computing power to produce 3D maps of galaxies. The Giant Arc was discovered first. It spans 3.3 billion light-years. The Big Ring was announced earlier this year. It is about 1.3 billion light-years across.

The galaxies in both structures are all about 9.2 billion light-years away. That means we’re seeing them when the universe was just one-third its current age. And the Giant Arc wraps around the Big Ring. The combination suggests the two are related.

So far, there’s no real explanation for these giant structures — nothing seems to fit all the observations. So scientists will keep on looking — trying to explain why the letters are clumping together in the cosmic alphabet soup.

Script by Damond Benningfield