Is There Anybody Out There?

One of my most engaging hobbies since I was about 11 years old has been reading science fiction stories. For me, one of the most interesting subjects of science fiction is speculation about forms of life that may live on other planets, either within our own solar system or on planets orbiting some distant star. I am especially interested in the possibility of intelligent life that human beings might someday encounter. As you might imagine, I have long been a fan of the original Star Trek series, its various sequels, and movies. However, I have often been amused by the aliens who invariably look human, with minor differences in ears, eyebrows, skin color, etc. There was the occasional alien who looked like an animated rock, a gaseous cloud, or a bright light, but these were rare. Gene Roddenberry, the creator of Star Trek, did address this issue. The problem was in part a lack of money for special effects. However, a more important issue for him was that he wanted the audience to be able to readily identify with alien characters. An animated rock or a gaseous cloud could not convey emotions.

It has been obvious to me for a very long time that an alien life form need not look like a human or humanoid to possess intelligence. There are indeed highly intelligent life forms on our own island in space that bear little outward resemblance to human beings. Whales and dolphins are excellent examples. Dolphins, due to their smaller size, are the easiest to maintain in an artificial environment where their behavior can be observed and studied in detail. It is difficult to assess the intelligence of a dolphin, however, researchers are making the attempt. It has been well established for years that dolphins communicate with each other. They "speak" in very complex patterns of clicks and whistles. They hunt for food in groups, using patterns of behavior that appear to require some degree of planning and forethought. Also, they are extremely curious, and they can learn new behaviors very quickly. I do not presume to posit that dolphins are as intelligent as human beings, however, I do not think that the limits of their intelligence have been established yet. It is an open question that will require a great deal of future research.

Now, lets consider a creature that is vastly different from a human being or a dolphin, both of which are vertebrates and mammals. The octopus is indeed a very different sort of creature. It is a mollusk, an invertebrate whose close relatives include oysters, clams, snails, and slugs. Yet unlike its relatives, the octopus is a very intelligent creature. They possess the ability to nearly instantaneously change their color, either uniformly or in complex patterns, to match their surroundings, enabling them to hide from potential predators. Octopi also appear to communicate with each other by flashing rapid changes of color in territorial struggles or to facilitate mating. This ability requires very good eyesight, as well as, a very complex brain and nervous system. Another aspect of octopus intelligence involves their ability to interact with their environment and solve problems. Each of the eight arms of an octopus can be controlled with very high dexterity. They can move heavy rocks or gently manipulate tiny objects. I have seen a documentary of an octopus that was presented with a glass jar with a screwed on lid. Inside the jar was a live crab, which was a favorite food of this particular species of octopus. The octopus spent several minutes turning the jar over and trying to get to the crab. The octopus seemed to be trying to figure out the problem. After a while, the octopus somehow got the notion to rotate the lid. Perhaps this was just dumb luck, but that octopus finally got the lid off that jar and ate the crab. I was astonished! As proof that the octopus had the ability to learn and remember, the same diver returned the next day and found the same octopus in its lair under a rock. The diver presented the octopus with another sealed jar containing a crab. This time, the octopus immediately grasped the jar, unscrewed the lid, and ate the crab. It had indeed learned and it did remember!

Well, the point of this exercise was to establish the reality of intelligent creatures having an appearance very different from a human being. Accordingly, if we ever do encounter an intelligent extraterrestrial life form, I would not expect it to look like us. Speculation about intelligence elsewhere in the universe is intriguing. However, a more practical pursuit for the near future is to attempt to answer a far more basic question. Is there reason to believe that any live exists beyond our planet? My intuition says yes, but as yet, there is no proof. The next few decades will be very interesting in terms of probes searching for signs of life within our solar system. A probe currently orbiting Mars has recently detected methane in the Martian atmosphere. Methane can only exist as an atmospheric gas for a few years. After that, it is broken down by solar radiation into simpler molecules. A major source of methane on Earth occurs as a byproduct of cellular metabolism of various microbial fauna. Methane can also be released by volcanoes, however, Mars is, by all indications, a geologically dead world. There has not been an active volcano on Mars for millions of years as demonstrated by the high number of large and intact meteor impact craters present on the extinct Martian volcanoes. Geologically recent volcanism would have covered over these features. Thus, the Martian atmospheric methane may be an indication that Mars currently supports, at least, microbial life!

What of other solar system bodies? Some scientists believe that the Jovian (Jupiter) moon Europa may be a likely candidate for some form of life. The entire surface of Europa is covered by ice that has a thickness of several miles. This was apparently determined by radar scans of the moon by the Galileo Probe. There is some evidence that a liquid ocean may exist beneath this ice. The Jovian moon Io, the closest to Jupiter of its four major moons, is very hot and volcanically active from Jupiter's radiation and from gravity induced tidal flexing caused by its proximity to Jupiter. It is most likely unsuitable for any form of life. Europa is farther away from Jupiter, but it may have enough energy imparted to it by its giant companion to allow for liquid water beneath its icy surface. On Earth, there are very complex ecosystems that surround hot water vents located in the oceans far below the depth that sunlight penetrates. These vents have been found along the mid-oceanic ridges in the Atlantic that mark the place where the continents are spreading apart. Along these ridges, new oceanic floor is slowly being formed on either side, as the continents move apart, and the Atlantic ocean widens. This new ocean floor begins as molten rock that is extruded from the Earth's mantle. The heat from this molten rock powers the vents. Along with hot water, the vents pour out a rich chemical mixture, some of which can be harnessed by bacteria as food. This forms the basis for a food chain that is independent of photosynthesis. A similar food chain could theoretically exist in the ocean of Europa.

If we can find life elsewhere in our solar system, the possibility of life in the neighborhood of other stars becomes much more likely. If this is the case, there may well be somebody out there. What do you think?