If we were somehow able to look down on the universe from above, what would it look like?
I suppose we should first talk about what makes up the universe. As we all know, the Milky Way galaxy is our home. It is a barred spiral galaxy somewhere out in the cosmos. We can't call it the center of the universe, because we don't know for sure where the center of it is. And, as you'll see a little while later, the universe, as we know it, doesn't have any real geometric shape, like a triangle or sphere.
So we have our galaxy, which is about 100,000 light years across. If you recall from previous discussions, a light year is the distance light can travel in a year, so it would take about 100,000 years for light to travel from one end of our galaxy to the other. Our major galactic neighbor, the Andromeda Galaxy, is about 2.5 million light years away, meaning it would take you 2.5 million years to get there at the speed of light. That also means we essentially are seeing the galaxy as it looked 2.5 million years ago.
The Milky Way and Andromeda galaxies are members of what we call the Local Group, which contains somewhere around 50 galaxies in one very small corner of the universe.
It's time to think even bigger.
This Local Group of galaxies is part of an even larger group of galaxies, called the Virgo Supercluster. The Virgo Supercluster is about 100 million light years across.
The universe is very big. Yeah, understatement of the year ... but it's gotta be reiterated.
The Local Group, when combined with other clusters, is actually part of an enormous supercluster astronomers call Laniakea. The supercluster is appropriately named because Laniakea translates to "immeasurable heaven." This incomprehensibly large network of galaxies is about 500 million light years across.
Seen from the outside, what would Laniakea look like?
The best description would perhaps be similar to one of those feathers you pluck out of your feather pillow on your bed. There is a "stem" where galaxies are concentrated, and then filaments extending out from the stem in all directions. It is actually quite beautiful, even if we may not readily see design in it.
And outside of Laniakea, there are likely other enormous groupings of galaxies. The human mind cannot begin to fathom the vastness of the universe, which contains a trillion or more galaxies.
Immeasurable heaven, indeed.