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Is ours the only universe? Is ours the only universe? Astronomers Chris Palma and Jane Charlton answer:Palma: There's a distinction that needs to be made here. When we loosely throw around the term "universe," usually what we mean is the observable universe, what we can see from here on Earth. We know roughly how old the universe is -- the current number is 13.7 billion years. And we know the speed of light. So anything that is within 13.7 billion light years from Earth we can see because light from that object has had enough time to reach us.
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