8. Age of the Universe

Scientists pretty much agree on the general method by which the early universe evolved. But they start to argue when the topic of the universe's actual age comes up.

The age of the universe has been put at 12 billion to 15 billion years for some time now, but every few months a revision or refinement is announced. Hubble Telescope observations yielded in April an estimate of 13-14 billion years.

We can't say when a firm answer will be presented, but we can predict the likelihood of another estimate sometime in 2003.

(A related and even more vexing set of questions: What exactly happened at the beginning of the universe, and what existed before that instant? These are questions cosmologists will likely wrangle with forever, since no direct observations can be made of those time frames and therefore, presumably, no proof can come.)

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