Looking for Life in All the Wet Places

Water, water everywhere, Nor any drop to drink.” In this line from “The Rime of the Ancient Mariner,” Samuel Taylor Coleridge describes the plight of stranded sailors, but he could be describing the universe. Liquid H₂O is probably the second most abundant compound in the universe (first is silicate, the stuff most rocks are made of).

H₂O is in the atmospheres of cool stars and even in the otherwise empty space between stars. In the solar system, we find H₂O on planets, many of the moons (orbiting astronomical bodies known by astronomers as natural satellites) of the planets, and in asteroids and comets. For a long time, astronomers thought that earth’s moon had no water, but in recent years they have found evidence of water even in lunar soil.

This “water, water everywhere” may be a consequence of the original creation as described in the first few verses of the Genesis 1 creation account. The second verse says that the initial creation consisted of “formless and void” water. On day two, God separated the waters above and below by an expanse (Genesis 1:6–8). This expanse is probably what we call the atmosphere and space. God made the astronomical bodies and placed them in the expanse on day four (Genesis 1:14–19). If God made the astronomical bodies from the waters above, it is no surprise that water is abundant among them.

Because water is deemed essential for life, secular scientists view the discovery of H₂O on planets as a hopeful sign that life might exist on those planets. But does water necessarily indicate the presence of life?

The Search Is On

In space, water is always in the solid or gaseous state. To detect the presence of water, astronomers often use a spectrograph to break up the light their telescopes receive into different wavelengths. Atoms and molecules absorb or emit light at certain wavelengths in the spectrum of light astronomers observe. Each element or compound produces a unique spectrum, so astronomers can identify elements and compounds, such as H₂O.

Scientists have found evidence of H₂O on both Mars and Venus, the most earthlike planets in the solar system. For many years, secular astronomers held out hope that life might exist on one of these planets. However, Venus is far too hot and chemically harsh to support life, and Mars is far too cold. A small amount of water vapor is present in the thin, frigid Martian atmosphere, and strong evidence points to ice in Martian soil and rocks. But Mars features no liquid water, and only the most optimistic secular scientists think that life may exist there.

Water vapor is found in the atmospheres of the solar system’s outer planets, but the conditions are not considered conducive for life. In recent years, scientists have expressed interest in some of the outer planets’ moons. The surface of Europa, one of Jupiter’s Galilean moons, is made of ice. Some features of Europa’s surface even look much like those of Arctic Ocean ice. Because these Arctic features are formed by water moving underneath the ice, many scientists think a vast ocean of water may swirl under Europa’s icy surface. Or consider Enceladus, one of Saturn’s moons. During its mission, the Cassini spacecraft orbiting Saturn photographed geysers erupting on Enceladus, indicating that water likely exists beneath its surface.

Does Water Indicate Life?

The temperature of any subsurface water in the moons of planets is probably much too low for the biochemistry of life. Furthermore, living cells are machines that harness energy to thrive. On earth, the source of that energy is sunlight, available in abundance. But the moons of the outer planets are very far from the sun, greatly reducing the amount of sunlight reaching them. And any possible liquid water would be far below the surfaces of these bodies, where sunlight does not reach.

The search for life in space is based on the knowledge that water is necessary for life, but it overlooks the many other factors that must be present for life to exist. It’s sort of like reasoning that since automobiles must have bolts, the discovery of a bolt is evidence of a car.

Since the search for life seems to have struck out in the solar system, scientists increasingly have shown interest in searching for life outside the solar system. About 25 years ago, technology reached the point where astronomers could begin to discover exoplanets, planets orbiting other stars.

Today, the number of known exoplanets exceeds 4,000. Scientists agree that most exoplanets are not suitable for life. However, they think a handful of exoplanets are the right size and are orbiting their stars at just the right distance (an area called the Goldilocks Zone) so that water may exist on their surfaces. So far, their search has come up dry.

Water and God’s Word

Why is the search for life elsewhere so important to many secular scientists? Most of these scientists are committed to naturalism, the belief that because there is no Creator or supernatural realm, nature is all that exists. Consequently, they believe life on earth must have come about through natural means. Many secular scientists insist that, if life arose on earth, life must exist elsewhere and is potentially abundant in the universe, though intelligent life might be relatively rare.

If life is unique to the earth, then the earth is exceedingly special. The distinctiveness of earth would have theistic implications as being designed by a Creator. Indeed, the Bible implies that at least human life, and perhaps all life, is unique to the earth. God revealed that earth, unlike other places in the universe, was created to be inhabited (Isaiah 45:18).

The Genesis 1 creation account says that God made all living things on earth. Genesis 1:26–27 tells us that God made man in his image and in his likeness to have dominion over the earth. And it was to earth that God sent his only begotten Son to take on flesh, die on a cross, and offer us salvation from our sins. God’s attention seems to be centered on man and our place in the cosmos—earth.

We could find oceans of water on other planets yet still find no life because water is not a life-sparking substance. Life can only come from life, not random, chemical reactions. All living creatures have their origin in the supernatural Genesis creation by the God who designed earth with the perfect amount of water for all manner of life to thrive and glorify the Creator.