Observable Universe: How Far Can We See?

The observable universe stretches about 93 billion light-years across.
We can see only as far as light has had time to travel since the Big Bang—13.8 billion years.
Because space expands, the most distant light we see comes from regions now far beyond 13.8 billion light-years away.
The cosmic microwave background marks the edge of what we can observe.
Beyond the observable limit, the universe continues—but it’s forever hidden from us.
The observable universe contains an estimated 2 trillion galaxies.
Every star, planet, and galaxy we’ve ever studied lies within this cosmic horizon.
As time passes, we’ll be able to see slightly farther—but expanding space will hide more distant galaxies.
Observing faraway light means looking back in time, nearly to the universe’s beginning.
The observable universe is our window into cosmic history—but not the full picture of all that exists.