The Passing of Halley's Comet by Samuel Phelps Leland

Review and Herald Publishing Association · Takoma Park Station, Washington, D. C. · Jun 30, 1910

The Passing of Halley's Comet

By Samuel Phelps Leland

HALLEY'S great comet has doubled the cape of the sun, and has begun its long journey through the sky. For over thirty-eight years it will rush through trackless space at a rate of speed past our comprehension. It will stop at no way stations. After this long journey it will swing about in its celestial pathway toward our sun again. Its return will consume another thirty-eight years, provided it shall return at all. Should it have attained sufficient momentum in its present visit to carry it beyond the confines of our solar system, it may be seized upon by the attractive power of another sun, and may never return to us again. It is very probable that many comets have left our system forever, and that many comets from other systems have come to us. The journey which this comet is to make is a perilous one. It is attended with many dangers. Planets are scattered through the sky. They are sending out their attractive forces across the comet's path. They are dangerous highwaymen. They may draw the comet into themselves, or may convert it into a satellite to revolve around some primary. Comets are common visitors to our solar system. Over eight hundred have been recorded. Only a part of this number come to our sun. Many do not come inside the orbits of our outer planets. The inter-solar spaces are the comets' playgrounds. The great Kepler once said that comets are more numerous in the heavens than are fishes in the ocean. They are harmless wanderers in the skies. Photography and spectroscopy are now employed with profitable results in the study of these peripatetic wanderers of the sky. But, after all, this study is principally confined to the comets that visit our sun.

Until about 1680 little scientific effort had been made to determine the laws governing the movements of comets. In 1682, when the comet recently in our sky made its appearance, Halley, a co-laborer with Sir Isaac Newton, undertook to compute the orbits of about two dozen comets. The appearance of this one in 1682 determined him to direct his attention to it. He first identified it with the one of 1531 and 1607. After much labor in a field then new, he determined its path among the constellations, and computed its period, and the date of its return, late in 1758, or early in 1759. He had no hope of being alive at this date, but made his computation for the benefit of men yet unborn. In honor to him his name has been given to the comet. It was a complex problem to solve. The path of the comet would be in the midst of planets whose disturbing influences would assail the traveler. It was a new field. No one had attempted its solution. Yet so accurately did he master the problem, that he was only a few days from its actual appearance, seventy-seven years in the future. The comet passed its perihelion on March 25, 1759. Considering the fact that Uranus and Neptune had not then been discovered, the result was wonderful indeed.

The discovery by Newton of the law, which has been formulated into the theorem, that all matter attracts in proportion to its amount and in inverse ratio to the square of its distance, enabled him to estimate the influences correctly. He determined when the comet would appear, if it met with no delay; and having ascertained that Saturn would delay it 100 days, and Jupiter 518 days, making its period 618 days longer than he had calculated, he was enabled to fix its date of coming. No scientific prediction ever excited so much curiosity and wonder. The comet came, and traversed the course among the stars mapped out by him, and reached its perihelion on March 13, 1759, only a few days from his indicated time.

This daring prophecy opened a new field in astronomy. The history of this act invests Halley's comet with an especial interest. Astronomers now calculate the movements of comets, though to the public the process has lost much of its exciting interest. From such labors and results men get a broader and clearer view of the universe. They learn that everywhere is a perfect balance;—that “all are but parts of a stupendous whole;” and that a law, once discovered, applies to all manifestations of matter, regardless of time or space. The Infinite Mind that planned the universe placed all of its parts in perfect balance. Harmony prevails everywhere; and when once we see a part, we can calculate all other parts, and can catch glimpses of the harmonious system in its entirety.—Samuel Phelps Leland, A. M., Ph. D., LL. D., in Christian Herald.