The observable universe is a sphere around Earth containing everything we can currently see. Because light has a speed limit, we can only see objects whose light has had time to reach us since the Big Bang (about 13.8 billion years ago).
: In this model, if you travel in one direction long enough, you eventually end up back where you started . There is no "outside" because the fabric of space-time itself is all that exists. Beyond the universe
Some modern theories suggest our entire universe is just one "bubble" in a much larger sea. The observable universe is a sphere around Earth
: Our universe could be an isolated "island" floating in a higher-dimensional "super-universe". What's Beyond The Observable Universe? There is no "outside" because the fabric of
: Most cosmologists believe that if you traveled past this "horizon," you would just find more galaxies and stars stretching on forever.
: A common misconception is that the universe expands into something. In reality, space itself is stretching ; it doesn't need "empty room" to grow into. 3. The Multiverse and "Super" Universes