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Science: Another End

2 minute read

Disdaining the possibility of invasion by hypothetical Martian monsters, astronomers and physicists have amused themselves and bemused laymen in recent years by formulating several ways in which the world may come to an end through the operation of natural law. One possibility is .that the sun may flare up as a nova, (“new star”), increasing enormously in temperature and brightness like scores of novae which have been observed at greater distances. Such an explosion in the sun would burn men and their Earth to a crisp.

Another prospect is that the moon, revolving around Earth, will eventually spiral so close that it will first raise huge, destructive tides in the seas, then break up, showering the earth with great lunar fragments.

A once popular idea of the world’s end is that the sun, like a glowing coal, will simply become too cold to support life on earth. This is oldfashioned. According to Dr. George Gamow, top-notch atomic physicist of George Washington University, the sun will get hotter before it gets cooler.

A theory which currently enjoys scientific favor is that the sun continues to radiate by converting hydrogen into heavier elements, mainly helium. A small part of the mass of the converted atoms is transformed into energy according to the Einstein equation.* Thus the sun’s supply of hydrogen is being constantly depleted.

Dr. Gamow’s calculations in quantum mechanics (mathematics of the atom) show that as the sun loses hydrogen, it converts hydrogen faster, thus slowly growing hotter and brighter. He puts the sun’s present hydrogen content at 60% of its total mass. In a Washington lecture last week, he declared that when the store of solar hydrogen drops to 1% or less, the sun will be 100 times brighter than it is now. By that time all terrestrial life will have been destroyed, the earth itself melted. Dr. Gamow added, however, that the cooking process will not become serious for several billion years.

*Energy equals mass multiplied by the velocity of light squared.

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