Morning journal and courier., 1882-01-06
The Dog Star.

In6 DOS Sb6Fs
 Sirius and the Worlds That Circle | Round Him.
 1 Richard A. Proctor in the Youths Companion.I i During the winter months one star can be
 seen to the right of the glorious Orion, but | lower down, which shines more splendidly
 than any other stars in the heayens-though
 not quite equal in brightness to either of the | two planets Jupiter and Venus. If is Sirius,
 the Dog star, and has in all ages excited the l admiration of all observers It IS supposed | by some that this splendid star has changed 1 in color during the last 2,O00 years, for an- 1 cient Greek and Roman writers spoke of It as
 red star, and Seneca even said that Sirius
 was ruddier than Mars. But most probably
 the red light referred to by those older writ CTS was simply that occasional flashing of red light from the star which you can see when ever Sirius is close to the horizon, vixen, as Tennyson writes,-
 . .. ''the fiery Sirius alters hue And bickers into red and emerald" When you have learned what Sirius really
 is, you will see how unlikely it is that he can
 have changed in color within 2,000 years,-a period which seems long to us, but is really
 as nothing in the lifetime of star. But what is Sirius? Does the telescope,
 which seems to bring far objects near, tell us anything about him, as it does about Jupiter,
 Saturn and the other planets The telescope
 scarcely tells us anything. The largest yet
 made by man only shows Sirius as very bright star. Sir William He=schel tells us that when his great telescope with its four feet mirror was turned toward Sirius, the
 approach of the star to the field of view re-
 minded him of the approach of daybreak.
 But when the star fairly in view it show ed no globe like that of the sun It was still a 0f
 brighter than any star in the sky. And 1t is
 pretty certain that men will never be able to make telescope which will show the real
 body of this splendid star.
 Yet, for all this, we know quite well what Sirius is. He is sun like OUTS, only very much larger. He lies about eight hundred thousand times farther from us than the san; and we know that if the sun were set eight hundred times farther away than he is, he
 would only look like star, al clear night.
 He would be very faint indeed compared with Sirius, shining only with about one two hun dredth part of that stars light. Now, this does not exactly tell us how large Sirius is,
 because his great brightness may be partly due to the great splendor of his surface. A square inch of iron at a white heat gives out much more light than square inch of iron at red heat, and yet is not larger. So it
 may be that, though the surface of Sirius gives out so much more light than the sur face of the sun, it may yet not be much larg CT.
 Still it seems reasonable to suppose that
 sun which is so much more resplendent than our own has much greater surface. I do not think we shall be very far wrong if we suppose that the surface of Sirius is not more than twice as lustrous as that of our sun. Now, in order that you may see how
 large Sirius is compared with the great earth on which we live, l may mention that the planet Jupiter IS the giant of the solar sys- tenn, exceeding our earth in size even more, but not much more than the sun exceeds Jupiter. Suppose that Jupiter is represent ed by ball one inch in diameter, then the earth on which we live would be represented by ball rather less than 8 tenth of an inch | in diameter, the sun by ball some 10 inches l in diameter and Sirius by globe nearly three yards in diameter according to the l small size have given him, but more than
 five and one half yards in diameter, according to Sir John Herschel's estimate
 There is yet another way of forming an | idea of the vast size of that globe which yet,
 owing to its enormous distance, looks like bright point in our skies. The moon travels ! at distance from the earth of nearly 240, 900 | miles, so that the entire span of the moons orbit is about 4S0, GOO miles. Now the diame- ter of the sun is about 84O,000 miles So that if the earth were set at the center of the
 
 | distance from her, the whole of the moons l orbit would lie far within the globe of the sun.
 It may seem surprising, but yes it is true, I that although astronomers have not been able to see, still less to measure the globe of Siri- l us, they have yet learned what 1t is made of -at any rate they know some of it's materi- als. For instance, they know quite certainly I that there is iron in it Gin the form of gas) | and sodium and magnesium, and there are l also enormous quantities of the gas called | hydrogen. How this has been learned I could not very well explain here. I shall l only say that the study of the light of Sirius | has shown that part of the light given out by l his glowing orb is cut of by certain vapor-
 much as part of the suns light is cut of by vapor in our own air when the sun is rising or setting; and just as the ruddy color of l the sun at that time shows him to be shin ing through the yapor of water in the air so do certain peculiarities in the light of Sirius show that that light has passed drought the yapor of irons sodium magnesium and hydro gen.
 It has been learned also that Sirius is rush. ing through space at the rate of from 20 to 30
 miles in every second of time He carries along with him, no doubt, all the worlds which travel around his globe. But it must
 not be supposed that this rapid motion l changes his place among the stars in a way we can easily recognize. On the contary, so enormous is this suns distance that his l change of place can only be detected by
 means of very powerful telescopes, or else | after long periods of time.
 And this leads me to consider a singular l discovery which has been made about this l glorious sun. Of course it is to be supposed that Sirius, like our sun, has a family of
 worlds travelling round him. This set obser- vers looking for any companion body which l might travel round Sirius. For they saw that any such body, to explain the move ments of Sirius, must be very large, though
 of course they expected only to find it much long time they could find no such companion.
 At last fine telescope with 8 glass Is I-2 inches in diameter, made by the celebrated optician Alvin Clarke of Cambridge, Mass, showed faint star close by Sirius,-that is,
 seemingly close, for in reality 1t was found
 to be at the very least 2,0OO millions of miles
 from him. Later the French astronomer
 Goldschmidt with much smaller telescope,
 claimed to have detected five other compan- ion stars, and was recently told by Prof
 Pritchett of Glasgow, Mo, that with a fine
 12-inch telescope by Alvin Clarke, he had
 seen two of these. He could not understand, however, how Goldschmidt could have seen
 them with a smaller telescope, as they were | among the faintest stars he had been able to
 detect with his powerful instrument. If
 these companion stars are really worlds at tending Sirius, and shining only by reflected light, they must be enormous bodies The | system of Sirius must in that case as far sur i'm E1-z