For as long as records have been kept, men have wandered about the cosmos. What is out there? Where does it all come from? How did the universe come about? Such inquiries have served as roots for many of our dearest myths. The announcement last week of the discovery of a planet outside our solar system, and the attendant apathy which accompanied it, prompted this writer into investigating the question of why men should care about the heavens at all.
Perhaps the primary reason for man's curiosity about the cosmos is that, to use a trite phrase, it is the final frontier. For while there are few new lands on the surface of the earth left undiscovered, the vastness of space is sure to defy any attempts at comprehensive exploration. As far as mankind is concerned, space may as well be infinite, even if in fact it may not be so.
The immense magnitude of interstellar dimensions is hard for the human mind to grasp. For example, we are used to thinking of our planet as vast, as is indeed true for most of our purposes. It would take a light photon, the fastest thing there is, just under a second and a half to circumnavigate the equator. It would take the same light ray eight minutes to cross the void separating the sun and the Earth, and 2.2 million years to reach us were it to start out from the Andromeda galaxy. Yet the Andromeda galaxy is not unduly distant as stellar objects go.
The universe is not extreme only in the distances between its contents, however. To be told that our sun is so large that it would comfortably contain a million Earths is enough to give one pause. What reaction can there be to the fact that our sun is fairly average as stars go, with stars having been observed a thousand times larger? The temperature of our gentle giant is a mild 8,000 degrees Fahrenheit at the surface, rising to a hellish 27 million degrees Fahrenheit at the center. By way of contrast, it should be noted that iron boils at a mere 5,400 degrees Fahrenheit.
And what of the other exotic phenomena which space presents us with? There are neutron stars, whose material is so dense that a teaspoon would weigh in the tons. There are supernovae, when stars explode, and in the process often radiate in a few days more energy than our sun would given a hundred million years. The possibility of the existence of black holes, objects whose gravitational attraction is so strong even light cannot escape their grasp, is taken very seriously by the scientific community.
And yet, even taking into account the wonders of the visible cosmos, of which only a small few have been detailed above, the speculations of cosmologists carry one into the consideration of even more exotic objects and ideas. For instance, most of us have managed to reconcile ourselves to the idea of four dimensional space-time, even if we don't really know what this means. Yet, if we are to believe some cosmological theories, space consists not of four, but 10 dimensions, with the other six "tucked away" so tightly that we cannot observe them. Still other speculations suggest the possibility that our universe is only one of an infinity of universes branching and budding off from each other.
The universe is wonderful, this much we know. But what is heaven that man should be mindful of it? One reason is that the heavens hold the key to many of the questions which reflective individuals have wrestled with for millennia, the big questions of our origins, our present condition and our future. Current physical theories tell us that the universe has a finite, albeit a great, age. This naturally leads the curious to ask "What was there before our universe? Did time start with the cosmos? Why did the universe come into being at all? Will the universe come to an end?"
To the last question at least, modern science seems to give an answer, namely, yes, in one way or another. Either the universe will eventually implode on itself, or the dissipation of energy will lead to the heat death of the cosmos. It thus seems that death does indeed come to us all.
Another reason why man must mind the heavens has to do with his own built-in urge to wander. We are by nature a restless species, ever on the lookout for new and exotic lands, but our planetary surface no longer offers the mysteries it once did. It is true that we scarcely know our oceans, but it is reasonable to expect that the day is coming when we will know them all too well. There is only one place left for the restless and adventurous to turn, and that is to space.
One could go on about the possible future material benefits of space research, but I will not, because I think the enterprise still worthy of our efforts even if we never get any satisfaction from our knowledge but the satisfaction of knowing. An understanding of the heavens can only help us to see our relation to the rest of the universe more clearly, and this is a worthy goal in its own right.
