Matter | Pages 74-75 | See Linked Version | |||||
apply those rules to a host of chemical processes on Earth, such as predicting the noxious compounds that form when car exhaust drifts into the atmosphere. The rules work equally well in space. For instance, astrophysicists can determine which elements combine in cooling interstellar gas clouds. The new molecules created in this way eventually lead to new stars and planetary systems. The periodic table is so basic to understanding the chemistry of the cosmos that a panel of physicists, archeologists, artists, and sociologists recently devised a surprising way to use it. The panel was charged with creating warning systems for the Waste Isolation Pilot Plant (WIPP), an underground storage facility in New Mexico for low-level radioactive waste. The experts had to envision systems that would warn people against digging at the WIPP site for at least 10,000 years because its contents will stay hazardous for that long. Languages and cultures are likely to come and go in that time, but WIPP will remain. Panel members designed frightening sculptures, earthworks, and other symbols of danger. They also proposed a chamber containing an engraved reproduction of the periodic table, with highlights marking the squares for uranium, plutonium, and other radioactive elements. Any future scientists would recognize the hazard, the panelists reasoned, because the periodic table is likely to endure. The Scarcity of MATTERThe periodic table is a tool for us to understand how matter behaves, and Rutherford's model of the atom helps us realize that all matter is mostly empty space. We also have seen that matter is rare in the universe--just a few atoms per cubic yard of space, on average. But by a different reckoning, it seems there is plenty of matter to go around. There are perhaps 100 billion galaxies in the universe, each containing perhaps 100 billion stars. Every person on Earth would have to count five stars per second for about 10,000 years to tally all of those stars, not to mention the atoms that compose them. How is it possible for so much matter to add up to so little? The key is to grasp the vast distances between objects in the universe. Just as we constructed a model of an atom with a tiny ball bearing in the center of the Louisiana Superdome, we can imagine scale models of planets and moons in our solar system, stars in our galaxy, and groups of galaxies in the cosmos as a whole. | |||||