E.J. Öpik (right) demonstrating his `Rocking Camera' with which he was able to determine the speed of meteors as they passed through the Earth's atmosphere. He had a life-long interest in the smaller bodies of the Solar System, and on his eighty fifth birthday, in 1978, a new minor planet, Planet Öpik, was named after him.
Some family information is available in the memoir for his brother, Armin Alexander Öpik.
"In the current era of the sun's and the earth's history, beginning about 500 million years ago, the average global temperature has been about 72 degrees, aside from the brief ice-age interludes. When our ice age ends a few million years from now, it will return to that level. Thereafter, the sun will resume its warming trend, raising the earth temperature at the rate of one degree per 100 million years at first and accelerating the warmup as time goes on. A billion years or so from now the average temperature will be 100 degrees - too hot for human life as we know it. Indeed, life for any sort of organism will have become impossible in the tropics and may be supportable only in the neighbourhood of the poles. Some 82 million years later, if our timetable is correct, the output of heat by the sun will be more than three times what it is now, and the average temperature on the earth will be above the boiling point of water.
"These future developments are a matter of only philosophical interest to the human race. Man has existed on this planet for only a million years, and if we are to judge by the transience of other species of living things, we can hardly expect our species to endure for more than 100 million years. It is possible, however, that some new species of intelligent beings will be living on the earth at the time of the coming heat wave. If so, they may be able to make a technological adaptation to the heat - perhaps some kind of "air conditioning" on a global scale. They will have millions of years at their disposal to work out the methods.
"The picture of gradually warming climate, broken by ice ages at long intervals, gives us a new perspective on the evolution of life on the earth. In all liklehood, before half a billion years ago the ice ages were so severe that they extinguished all life on the earth. If, for instance, the sun's heat output during an ice age fell about 17 per cent below normal, as it has in more recent times, then the average earth temperature during the Algonkian ice age 750 million years ago must have been low enough to cover the whole earth with glaciers. Therefore after each of the early ice ages the evolution of life must have had to start again from the beginning. The intervals between ice ages were not long enough to allow the higher forms of life to evolve.
"Apparently the Eocambrian ice age 180 million years ago was the first in which the entire earth was not covered with ice. For the first time in the history of the earth the tropical belt remained ice-free, and life could take refuge there. This means that life has had 750 million years (since the Algonkian ice age) to continue uninterruptedly its glorious march of evolution. If our hypothesis is correct, it will have many hundreds of millions or years more to go on to still higher levels of evolution."
Last Revised: 2009 November 18th