Everything We Can See

The observable universe is staggering in scale but finite in reach:

• It spans 93 billion light-years in diameter, centered on wherever you stand
• It contains roughly 2 trillion galaxies with more stars than grains of sand on Earth
• The CMB is the oldest observable light, emitted 380,000 years after the Big Bang
• The expansion of space is accelerating due to dark energy
• In the far future, distant galaxies will cross the cosmic horizon and vanish from view

The observable universe is not the whole universe. It is just the part whose light has had time to reach us. What lies beyond may be identical, wildly different, or infinite — and we may never know.