The Universe isn’t just a random scattering of galaxies sprinkled throughout an expanding void. The closer we look, the more we see that there are structures — some of which are incomprehensibly vast groupings and clusters of galaxies that are gravitationally bound together.
Such a structure has just been discovered arcing across the southern edge of the sky, and it’s a colossus, spanning an immense 1.37 billion light-years from end to end. Its discoverers have named it the South Pole Wall.
Although the size is remarkable — it’s one of the largest structures in space we’ve ever seen — we know exactly what the South Pole Wall is. It’s a galaxy filament, a huge formation of galaxies that forms a border between the empty spaces of cosmic voids that together form the cosmic web. Hence, we call it a wall.