THE SUN,
With its immediate attendants, Mercury, Venus, Earth, Mars, etc., has been the “theme of our discourse” for the last eighteen months. Except an occasional reference to one of the planets as being located near some fixed star, or in some constellation, little has been said about the 3,391 “fixed” stars, visible to the naked eye, many of which are located on maps of the heavens, just as villages, cities, mountains, rivers and plains are located on maps of the earth; nor of the somewhere between 30,000,000 and 50,000,000 which are visible only through powerful telescopes, and whose distances from the sun are so great as to make that of Neptune appear like a little walk “across lots” to visit a neighbor. Nor is it proposed now to enter upon such an extensive subject, except so far as may be necessary to present a single thought. As we know, our sun is a bright body, whose light and heat (so great is their power) we can hardly estimate. Both these qualities render it visible to us and make us realize its presence. The other bodies, as Mars, Jupiter and the Moon are seen only by reflected light, and were they as distant as the fixed stars, would not be at all visible. These 30,000,000 to 50,000,000 stars must be suns. How many satellites has each? We do not know, for they can not be seen. Suppose each had as many as our sun. Then instead of 30,000,000 to 50,000,000 of heavenly bodies, we have within reach of the telescope from 240,000,000 to 400,000,000. How many are outside of these? No man can number them. We shall have to wait till our minds can grasp the infinite. Are these millions of bodies standing still, or are they in motion? Does our sun stand still and permit us to go around him once every year, or is he, and are we along with him, making our way through other vast multitudes and moving around some other central orb? Observation proves that the sun is only a sergeant in a great army of generals, and marches his squad in an appointed way to their assigned duties. How do we know? The records of patient watchers for centuries reveal the fact. “If we suppose the sun, attended by planets, to be moving through space, we ought to be able to detect this motion by an apparent motion of the stars in a contrary direction, as when an observer moves through a forest of trees, his own motion imparts an apparent motion to the trees in a contrary direction. All the stars would not be equally affected by such a motion of the solar system. The nearest stars would appear to have the greatest motion, but all the changes of position would appear to take place in the same direction. The stars would appear to recede from that point of the heavens toward which the sun is moving, while in the opposite quarter the stars would seem to crowd more closely together.” Proceeding upon this principle, Sir William Herschel was in 1783 enabled to announce that the observed proper motion of a large portion of the stars could be accounted for on the supposition that the sun was moving toward the constellation Hercules. Later investigations not only established the fact that the sun moved, but that it was moving nearly toward the star Rho, in Hercules, and Struve estimated its motion at about five miles per second; though Professor Airy places it at about twenty-seven miles per second. It is also highly probable that its motion is not in a straight line, but in obedience to the same laws that govern the motions of its own satellites, it with other suns revolves about a center located nearly in the plane of the Milky Way, and with an orbit so great “that ages may elapse before it will be possible to detect any change in the direction of its motion.” Meantime, finite beings are interested in knowing how its light and heat affect their interests, and how these qualities may be made most profitable to mankind. For ourselves, we must at present be content to know that on the 1st our sun has reached a point 4° 48′ north of the equator, and that by the 30th he will be 14° 58′ north, an increase in northern declination of 10° 10′, and, as a consequence, our daylight will be increased about one hour and thirteen minutes, and the time “from early dawn to dewy” twilight will be seventeen hours and thirty-five minutes. On the 1st sunrise occurs at 5:43 a. m., sunset, 6:24 p. m.; on the 16th, sunrise, 5:19, sunset, 6:40; on the 30th, sunrise, 4:59, sunset, 6:54.