The Universe can outrun light without breaking Einstein’s rules
The observable universe appears larger than its age in light-years because space itself expands, allowing distant regions to move away from us faster than the speed of light. This phenomenon does not violate Einstein's theory of relativity, which only limits movement through space, not the expansion of space itself.
Why it matters
Understanding cosmological expansion is fundamental to modern astrophysics and our grasp of the universe's structure.
An expanding universe makes measuring distance more complicated because space does not remain fixed while light travels through it. Galaxies continue to emit light, but that light may spend billions of years crossing the cosmos before reaching us. During that journey, the universe keeps expanding, increasing the average separation between galaxies (yes, I know that sometimes galaxies can collide, but we're talking on average, at big scales here).
This means that when a telescope captures the light from a distant galaxy, the image does not reveal where that galaxy is today. It shows the galaxy as it appeared when the light began its journey. To estimate its present distance, astronomers must use a cosmological model that accounts for how the universe has expanded over time.
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