1. Why do some scientists say it is almost certain that life exists on planets in other solar systems and other galaxies?

This idea, much publicized in the mass media, hinges upon two evolutionary theories. These are the assumed evolution of the solar system and of our galaxy from a cloud of gas and dust, and the assumed evolution of life on earth from chemicals. Neither theory can be scientifically demonstrated to be true, but if they were true, certain logical conclusions would follow:

a. In the universe billions of stars similar to our sun are assumed to have evolved in the same way that our sun supposedly did. If this is true, millions of planets quite similar to the earth and having similar atmospheres, climates, etc., must likewise exist.

b. Since life supposedly evolved under these conditions on our earth, life must also have evolved on many of these other planets, developing some species as intelligent as or even more intelligent than man.

It is important to remember, however, that no scientific evidence whatsoever proves that any other planet similar to our earth exists anywhere in the universe. The whole idea of life on other planets is pure speculation without a shred of scientific evidence. Stanley Miller and Leslie Orgel in their honest and admittedly biased book, The Origins of Life on the Earth, listed the different assumed quantitative factors used by eminent astronomers Harow Shapley and Carl Sagan in their independent estimates of the probability that intelligent life exists on other planets. Included is a column in which the reader can write in his own assumed values and calculate a probability. Miller and Orgel explained, "Also included in the table is space for the reader to put in his own numbers. These can be considered as reliable as the other two estimates."¹ Nevertheless, the notion is so popular with both scientists and lay people who want evolution to be true, that millions of dollars of tax monies have actually been spent using radio telescopes to listen for intelligent messages from outer space. God could have created life on other planets, but He has given us no evidence of it, either through science or in the Bible.

a. The sun's temperature is right to provide the range of light wavelengths suitable for life. Higher temperatures would result in too much ultraviolet radiation, lower temperatures in too much infrared.

b. The sun is at the correct distance from the earth and has the proper size and temperature to provide the total amount of radiation required to maintain surface temperatures on earth suitable for life. Even small changes in any of these factors would probably destroy all life.

c. The nearly circular orbit of the earth limits temperature variations.

d. The water vapor and carbon dioxide in the atmosphere produce a so-called "greenhouse effect" which moderates the temperature extremes.

e. A high altitude ozone layer effectively absorbs the lethal fraction of solar ultraviolet rays which would destroy life on the earth's surface were the ozone layer removed.

f. The 23½.degree inclination of the earth's axis of rotation from the perpendicular to the plane of its orbit provides for the seasons. It probably also considerably increases the land area in the northern hemisphere suitable for intensive summer agriculture.

g. The earth's magnetic field, extending tens of thousands of miles into space, shields the earth's surface from much of the cosmic radiation which probably would prove deleterious to life.

h. The lunar gravitation produces important tidal circulation effects in the oceans, which make conditions much more suitable for sea life, especially in the shallow zones along shores and in estuaries.

i. The mass and size of the earth are adjusted to provide gravitational force and atmospheric pressure suitable for life, and also to prevent the escape of the earth's atmosphere.

k. The earth's surface is blessed with a concentration unknown any-where else in the universe, of liquid water, the only possible solvent and medium for living cells. The physical properties of water are unique and absolutely essential to all life processes. These properties of water include (1) the highest heat of fusion(melting), (2) a liquid temperature range which includes the temperatures at which enzymes and other life molecules can exist and function, (3) the highest heat capacity(heat required to increase its temperature), (4) the highest heat of vaporization, (5) the highest dielectric constant of all of the common liquids, (6) the greatest solvent powers, (7) the greatest power to form a special chemical bond called a hydrogen bond, (8) the greatest ionizing power of all the common liquids, (9) the property (unique except for bismuth) of expanding when it crystallizes, and (10) a strong power to absorb infrared radiation.

Liquid ammonia is sometimes proposed as a possible liquid for some imagined kind of life system. It has slightly higher values in several of the above properties, but it is distinctly inferior to water in the others. The idea of life in any solvent other than water is mere fantasy.

l. The elements carbon, hydrogen, oxygen, nitrogen, and phosphorus, together with liquid water, are the basis for the only remotely possible chemical framework for life. The surface of the earth is the only known place in the entire universe where these substances are found in suitable quantities and in the proper forms for life to exist.

The ideal combination of conditions and factors essential to life observed only on earth surely points to intelligent, purposeful design. To believe that this beautifully balanced life support system which carries the human race safely at speeds of more than one thousand miles per minute through hostile space is a mere accident requires invincible faith in the power of chance. Would not any honest observer have to admit that the earth appears to have been designed for us to live on, just as David the Psalmist said?

"The heaven, even the heavens, are the LORD'S; but the earth He has given to the children of men."
Psalm 115:16

1 Miller, Stanley L. and Leslie E. Oregel, The Origins of Life On the Earth (Prentice-Hall, Inc., Englewood Cliffs, NJ, 1974), p. 214.

2 Meldau, Fred John, Why We Believe in Creation, Not in Evolution (Christian Victory Pub. Co., Denver, 1972), pp. 26-51.