10²⁴ meters = 1,000,000,000,000,000,000,000 kilometers

Jumping now to the almost unimaginable distance of 100 million light-years, you can clearly see clusters of galaxies and clusters of clusters (called, naturally, super-clusters).

But notice that the clusters are either clumped together in groups, or connected to one another by long thin filaments. And between them there are huge bubbles of absolutely nothing! The bubbles are called voids and contain the most perfect vacuum known—only one lonely atom per cubic meter.

You are actually seeing the very structure of the universe itself; a foamy texture often called the cosmic web.