Thursday, June 23, 2011

The New Astronomy

DAY THIRTY: Yesterday was a mild flu day for me and I took it real easy. However, I did feel up for doing some editing on the book of stories I'm working on. It's getting there!

Last night Ellen and I watched a PBS program, Journey to Palomar which was a fascinating documentary on the development of the large telescope in the late 19th and early 20th centuries, largely under the influence of George Ellery Hale. It began with the Yerkes Observatory - a 60-inch mirror - in Wisconsin; then the Mt. Wilson Observatory in Pasadena - a 100-inch mirror; and culminating in the 200-inch scope on Mt. Palomar, south of Pasadena. The vision, the effort, the challenges, trials, failures and triumphs of this whole story were riveting. Hitherto I knew very little about George Ellery Hale, but he has to be regarded as one of the heroes of modern science, and his influence on our present-day understanding of the universe is incalculable.

That program led me back to my favorite scientist of that era, Samuel Pierpont Langley. S.P. Langley could be called the first astrophysicist; his invention of the balometer, which measures the heat from a star (imagine that!), was a great breakthrough. He founded the Smithsonian Astrophysical Laboratory and devoted much of his life to study of the "solar constant," i.e., the question of how much energy from the sun reaches the surface of the earth, and whether that energy is relatively constant, or whether it varies significantly over time - an issue still hotly debated (no pun intended) in the whole global warming controversy.

He became "famous," when he turned his attention to flight. He was the first to achieve steam-powered, heavier-than-air flight, in 1896, with a large model airplane which remained aloft three minutes, flying almost a mile at 80-100 feet. Subsequent efforts by him to achieve manned, powered flight ended in failure; the last effort, in which the plane was catapulted over the Potomac River, December 8, 1903, was nine days before the Wright Brothers flew Kittyhawk. Had he been successful that day (and there are some who say that if the catapult had worked properly, he would have been successful), Langley's name would be a household word today.

Langley first came to my attention because Shirley's mother was a Langley, and the family oral tradition is that S.P. Langley is in the family tree somewhere. My son John has put considerable time and energy into researching Langley, and regardless of his failure in manned flight, we Crocketts regard him as one of the great scientists of the 19th-20th century. He deserves to be better known than he is. I hope that someday, someone will do a PBS documentary about him. His life and work are certainly as riveting, and possible as important, as Hale's, I believe.

Langley wrote a book, The New Astronomy in 1884, with several subsequent editions. The book was his effort to summarize for a lay audience the astounding developments in astronomy which were taking place a that time. It is beautifully written and well worth reading even today. It is filled with observations, about the sun especially, which are fascinating, lucid, and remarkably prescient. Here is an excerpt:

from The New Astronomy, by Samuel Pierpont Langley, written in 1884 – almost 130 years ago

…..From recent measures it appears that from every square yard of the earth exposed perpendicularly to the sun's rays, in the absence of an absorbing atmosphere, there could be derived more than one horse-power, if the heat were all converted into this use, and that even on such a little area as the island of Manhattan, or that occupied by the city of London, the noontide heat is enough, could it all be utilized, to drive all the steam-engines in the world. It will not be surprising, then, to hear that many practical men are turning their attention to this as a source of power, and that, though it has hitherto cost more to utilize the power than it is worth, there is reason to believe that some of the greatest changes which civilization has to bring may yet be due to such investigations. The visitor to the Paris Exposition of 1878 may remember an extraordinary machine on the grounds of the Trocadero, looking like a gigantic inverted umbrella pointed sunward. This was the sun-machine of M. Mouchot, consisting of a great parabolic reflector, which concentrated the heat on a boiler in the focus and drove a steam-engine with it, which was employed in turn to work a printing-press, as our engraving shows (Fig. 58). Because these constructions have been hitherto little more than playthings, we are not to think of them as useless. If toys, they are the toys of the childhood of a science which is destined to grow, and in its maturity to apply this solar energy to the use of all mankind.

…. It is pregnant with suggestion of the future, if we consider the growing demand for power in the world, and the fact that its stock of coal, though vast, is strictly limited, in the sense that when it is gone we can get absolutely no more. The sun has been making a little every day for millions of years, — so little and for so long, that it is as though time had daily dropped a single penny into the bank to our credit for untold ages, until an enormous fund had been thus slowly accumulated in our favor. We are drawing on this fund like a prodigal who thinks his means endless, but the day will come when our check will no longer be honored, and what shall we do then?

The exhaustion of some of the coal-beds is an affair of the immediate future, by comparison with the vast period of time we have been speaking of. The English coal-beds, it is asserted, will, from present indications, be quite used up in about three hundred years more. Three hundred years ago, the sun, looking down on the England of our forefathers, saw a fair land of green woods and quiet waters, a land unvexed with noisier machinery than the spinningwheel, or the needles of the "free maids that weave their threads with bones." Because of the coal which has been dug from its soil, he sees it now soot-blackened, furrowed with railwaycuttings, covered with noisy manufactories, filled with grimy operatives, while the island shakes with the throb of coal-driven engines, and its once quiet waters are churned by the wheels of steamships.

Many generations of the lives of men have passed to make the England of Elizabeth into the England of Victoria; but what a moment this time is, compared with the vast lapse of ages during which the coal was being stored! What a moment in the life of the "all-beholding sun," who in a few hundred years — his gift exhausted and the last furnace-fire out — may send his beams through rents in the ivy-grown walls of deserted factories, upon silent engines brown with rust, while the millhand has gone to other lands, the rivers are clean again, the harbors show only white sails, and England's "black country" is green once more! To America, too, such a time may come, though at a greatly longer distance.

Does this all seem but the idlest fancy? That something like it will come to pass sooner or later, is a most certain fact — as certain as any process of Nature — if we do not find a new source of power; for of the coal which has supplied us, after a certain time we can get no more. Future ages may see the seat of empire transferred to regions of the earth now barren and desolated under intense solar heat, — countries which, for that very cause, will not improbably become the seat of mechanical and thence of political power. Whoever finds the way to make industrially useful the vast sunpower now wasted on the deserts of North Africa or the shores of the Red Sea, will effect a greater change in men's affairs than any conqueror in history has done; for he will once more people those waste places with the life that swarmed there in the best days of Carthage and of old Egypt, but under another civilization, where man no longer shall worship the sun as a god, but shall have learned to make it his servant.

Samuel Pierpont Langley

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