From Plastics to Pulsars

Trying to understand the universe around them, some scientists have sought to unlock the secrets of the atoms and molecules that quite literally make up just about everything under the sun --and beyond it as well. Others have sought this understanding by peering into the remotest reaches of space. Both groups of explorers were recognized last week when the Royal Swedish Academy of Sciences announced the 1974 Nobel Prizes for Chemistry and Physics. It gave the chemistry award to Professor Paul J. Flory, 64, of Stanford University, for his studies of macromole-cules, or large molecules. The physics prize was awarded jointly to Professors Martin Ryle, 56, and Antony Hewish, 50, both of England's Cambridge University, for their accomplishments in the field of radio astronomy.

Scientists long suspected that polymers--macromolecules made up of chains of smaller molecules--might be custom-tailored to create an almost infinite variety of materials. Flory, who began his work 40 years ago as a member of the Du Pont research team that developed nylon, showed the way. He devised methods of analyzing and studying polymers that made it possible to develop new plastics and other synthetics on a systematic basis. He also found that there is a specific temperature (now known as the Flory temperature) at which each polymer exists in an ideal state for study of its properties. This discovery became the basis for the development of hundreds of different plastics and other synthetics.

Flory also identified other properties of long-chain molecules; for example, he determined the conditions under which they can increase the length of their chains, making possible a greater variety of synthetic materials. He discovered the phenomenon of chain transmission, in which one molecule that is growing, or adding units to its chain, can stop and pass its growing power on to another. Industrial researchers are using Flory's discoveries to develop fibers that may prove to have three times the strength of nylon but only a fraction of its weight. Flory, at Stanford since 1961, is currently studying the polymers in living organisms. Because skin, bone and muscle fibers are made up of long-chain molecules, his work could conceivably lead to the day when man will be able to simulate them in laboratories.

Little Green Men. The contributions of Ryle and Hewish, the first radio astronomers to win the Nobel Prize, are equally significant. Unlike astronomers who view the visible light from celestial objects through optical telescopes, they observe the invisible, longer wave lengths of energy given off by stars, galaxies and other heavenly bodies. To detect these so-called radio frequencies, they use radio telescopes--giant antennas that focus the incoming waves much as optical telescopes focus light waves.

Unfortunately, a radio telescope that could accomplish the equivalent of what, say, the 200-in. Mount Palomar telescope does optically would have to consist of a dish-shaped structure many miles in diameter--an obviously impractical requirement.

To overcome this problem Ryle, who was knighted in 1966 and named England's Astronomer Royal in 1972, conceived of simultaneously using several small and widely spaced radio telescopes only 10 yds. in diameter and zeroing all of them in on a celestial object.

As a result of his efforts, astronomers can now clearly "see" in radio frequencies objects that are billions of light-years*-- away, a feat that the Royal Academy equated to seeing a postage stamp on the moon with an optical telescope. Using Ryle's techniques, radio astronomers are extending their investigations to the very edge of the observable universe. Their findings are bringing man closer to an understanding of how the universe began and how it is evolving.

Hewish was cited for his discovery of pulsars, distant objects that give off regularly spaced bursts of radio waves. When he and his colleagues at Cambridge, using a radio telescope, first detected these pulses coming from a point in the sky, they suspected that they had picked up signals from intelligent beings in space--and promptly named the source LGM (for Little Green Men).

Radio Beacon. Further observations by Hewish and other radio astronomers soon put this tantalizing speculation to rest but eventually confirmed that a pulsar is a neutron star. Space, in fact, seems to be full of neutron stars. Since Hewish and his assistant, Jocelyn Bell, found the first one, about 100 more have been identified by astronomers. A neutron star is a bizarre object. It is formed when a giant star exhausts its nuclear fuel and collapses inward on itself, crushing much of its matter into a ball of neutrons some ten miles in diameter--but so dense that a thimbleful of it would weigh millions of tons on earth. Scientists theorize that the neutron star spins rapidly, causing its intense magnetic field to interact with ionized gases surrounding it. This results in a "beacon" of radio waves that periodically sweeps past the earth, producing the regularly spaced pulses.

Astrophysicists had postulated the existence of neutron stars in the 1930s but had despaired of ever discovering them; they were too small, scientists felt, for their light to be detected from earth. Hewish's observations confirmed that these strange bodies, conceived in the mind of man, really exist in the far reaches of space.

*A lightyear, the distance that light travels in a year, is about six trillion miles.

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