What I mean is. It’s only what we can observe, right? So is it like, there’s a big universe, and we’re shining a flashlight jnto it, and as the Earth and Sun move through the universe, we’re seeing different parts of the whole, and losing others? Or can we just see to an observable “edge” that isnt centered on us?
In: Planetary Science
The phrase “observable universe” refers to the region of the universe from which light could have travelled to us within the age of the universe. Anything outwith that region we can’t see because the light hasn’t reached us.
It does not mean literally only what you are currently observing. It is everything that is theoretically possible to observe, which is a sphere of radius ~46 billion light years.
There is the slight caveat in the discussion, as the early universe (first 300k years) was opaque, meaning light couldn’t travel through it due to all the dense plasma. This means that with light, you can only see as far back as 300k years, but as you could technically probe further with other means (neutrinos, gravitational waves), this is not the limit of “observation”.
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