But what many people may not be aware of is that scientists agree that the Earth has always been in the 'habitable zone' throughout its 4.6 billion-year history. Why should this be so interesting? Because all astronomers will tell you that the Sun gets hotter as it ages. For the Earth to always have had liquid oceans for the majority of it's history, geologists admit that there would have to have been "a remarkable fine-tuning of its atmosphere to a warming sun."
The following is an excerpt from p.100 of Science `83, July/August, concerning this:
"The climate of the Earth has varied considerably over time .... Yet what puzzles many scientists is not that the climate varies but that it has remained as stable as it has.
"The Earth, they point out, is quite literally poised between fire and ice. Consider, for example, what would happen if we somehow moved the Earth slightly closer to the sun.
"As the oceans grew warmer, more and more water vapor would begin to steam into the atmosphere ....
"In the end our planet would become a twin of unfortunate Venus, the next planet inward to the sun: a gaseous, dry searing hell, its surface covered with clouds, oppressed by a massive atmosphere of carbon dioxide, and hot enough to melt lead.
"Suppose, on the other hand, we moved the Earth further out from the sun. As the planet grew colder, glaciers would grind [toward the equator].... In the end, the Earth would gleam brilliantly—but its oceans would be frozen solid.
"Thus, the climate is balanced precariously indeed—so precariously that many geologists now believe that tiny, cyclic variations in the Earth's orbit, known as the Milankovitch Cycles, were enough to have triggered the ice ages.
"But geologists ... assure us that the oceans of the earth have remained warm and liquid throughout its 4.6 billion-year history.
"Perhaps this is a lucky accident—after all, if the Earth had not formed at just the right distance from the sun to have liquid oceans, we would not be here to worry about it. But the astrophysicists point out that things aren't quite that simple.
"The sun [as must ALL stars of this life-supporting type] they say, ... is inexorably getting hotter with age. In fact, it is about 40 percent brighter now than when the Earth was born. So how could the climate possibly stay constant? If the Earth is comfortable now, then billions of years ago, under a colder sun, the oceans must have been frozen solid. But they were not. On the other hand, if the oceans were liquid then, why has the sun not broiled us into a second Venus by now?"
The Science article concludes that if continuation of life on the Earth depended on an "accident" that has been
"followed by a remarkable fine-tuning of its atmosphere to a warming sun, then the hopes of finding other intelligence in the universe must be slim indeed."
On the contrary, doesn't it appear that the "accident" and the "remarkable fine-tuning" over billions of years provide evidence of another, much higher intelligence?
Earth’s Perfect “Address” (g 2/09 pp. 4-5; Watchtower Online Library)
THE EARTH - Was it “Founded” by Chance? (g00 10/8 pp. 8-11; Watchtower Online Library)
The "Impossible" Universe (Search For Bible Truths)
Why Do Some Scientists Believe in God? (Search For Bible Truths)
The Universe — Did It Come About by Chance or by Design? (Search For Bible Truths)
Is It Unscientific to Believe in God? (g04 6/22 pp. 3-4; Watchtower Online Library)
Our Awesome UNIVERSE - A Product of Chance? (g00 10/8 pp. 3-4; Watchtower Online Library)
Did the ELEMENTS Come About by Chance? (g00 10/8 pp. 5-7; Watchtower Online Library)
(To those who are not Jehovah's Witnesses (JWs), please remember that if you are looking for the authoritative information about the Watch Tower Bible and Tract Society's (WTBTS) Bible-based beliefs and practices, you should look to our OFFICIAL WEBSITE at http://www.jw.org/en. Numerous publications as well as the New World Translation Bible (NWT) and the very useful Watchtower Online Library can be found there.)