Observable universe (noun, “ub-SERV-uh-bul YOO-nih-vers”)
The observable universe is a huge bubble-shaped region of space around Earth. It contains all the matter and energy that we could, in theory, observe from Earth. The universe itself may go on forever. But the edge of the observable universe is like a cosmic horizon line that we cannot see beyond.
Why can we observe only a set region of space? Because the way we observe distant objects in the universe is by looking at the light they give off. This might be visible light. Or it might be radio waves, Read Entire Article
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