Not too long ago nor far away an astronomer was giving a lecture on the sun and planets. He happened to mention that the Sun was a yellow dwarf star and would have a moderate lifetime, burning out in about 6 billion years.

A terrified voice interrupted from the middle row in the back: "HOW MANY YEARS?"

"I said," replied the professor, "that the sun had enough fuel to last another six billion years."

"Thank God," said the voice, "I thought you said six MILLION."

It pays to have a sense of proportion.