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Show Hj I Lick Observatory Astronomer fl Explains Origin of These Astral Visitors. H' i j SEEN BY TELESCOPE H' Spiral Nebulae Dimmer Away Hr After Few Months and Then Disappears. BERKELEY, Cal., Dec. 14. Three H nejvborn stars, which blazed up as a B result o collisions, or other disasters, H In two far-distant spiral nebulae, and then within a few months dimmered B their fires until they could no longer ( H t be detected by the most powerful tele- : H scopes this is a discovery just an- i nounced by Astronomer Heber D. Cur-, tis of the Lick Observatory of the TJni-versity TJni-versity of California. He believes that It is perhaps 20,000,000 years ago these catastrophes occurred. But so vastly distant are these two spiral nebulae 1 that only now has the light sent forth B by these collisions completed its jour- ney through space and brought the news of "these catastrophes of the H: heavens that happened perhaps 20,- l 000,000 years ago. The special importance of the dis-1 dis-1 covery of these three "New Stars" in spiral nebulae is the evidence given in support of the belief that each of the spiral .nebulae outside the Milky Way is in 'itself an enormous universe of stars, comparable in vastness to the Milky Way, In which we dwell. That the Milky Way itself is a vast H spiral nebula is an opinion which is finding increasing support among the world's leading astronomers. Discovered at Lick Observatory Especially significant Is the fact that the3e three new stars now discovered at the Lick Observatory are in spiral nebulae, and not in our own universe of stars. Astronomer Curtls's discov-B discov-B cry doubles the number of new stars B discovered in spiral nebulae, since only three had previously been recorded, although twenty-six new stars have been recorded in our own galaxy, the Milky Way. No human eye has seen these three new stars they were found by Dr. Curtis by the examination of stellar -photographs. Recently Astronomer Curtis examined a photograph taken March 20, 1915, with the great Cross -ley reflecting telescope at the Lick Observatory. The subject of this photograph pho-tograph was the nebula known as N. G- C. -1527. There Astronomer Curtis found the image of a star which did not show on a photograph of the same region taken Two months earlier. Examination Ex-amination of a photograph taken a month later showed that this new star had grown fainter; on a photograph taken six weeks later it was barely perceptible, and then it faded from the telescope's photographic eye. Other Stars Found Both the other n-ew stars discovered by Astronomer Cur.tis were found in the same way by his examination of photographs of a spiral nebula' I known as N. G. C. 4321. The first of ; these. Nova A, was first photographed with the Crossley telescope at the Lick I Observatory on March 17, 1901, and; twice in the following month, but it 1 was not detected until this year, and ' by that time had long faded from pos- 1 slbility of observing or photographing. I The second new star in this same ' spiral nebula, Nova B, was photo- j graphed on March 2. 1914, with the Crossley telescope at the Lick Obser- , vatory, but not detected until this year, j Several photographs taken since April, 1915, reveal no trace of its presence. These new stars, of which announcement announce-ment has just been made in Lick Observatory Bulletin No". 300, are supposed sup-posed to have become visible because of increase of their light through some collision of heavenly bodies, and then within a few months to have so decreased de-creased in radiance as no longer to send forth enough light to affect the most delicate photographic plates, used with the most powerful telescopes. Notable in itself as is the discovery of these three newborn suns, which doubles the number of new stars thus far found in spiral nebulae, the greatest great-est value of the discovery is the op-1 iportunity it has afforded Astronomer I Curtis to strengthen the "island unl-! verse" theory of the spiral nebulae. "Island Universe" Theory I This "island universe" theory is that each of the spiral nebulae bevond our Milky Way Is in itself a vast "universe "uni-verse of suns, at an almost unthinkable distanco from our own universe the Milky Way. These new stars just found showed of an average brightness of about tlie fifteenth magnitude. A star of the fifteenth magnitude in our! galaxy would be at least twentv thousand thou-sand light years away that is to say, it would tako twenty thousand years for the light to come from such a star, although light travels at the rate of1 one hundred and eighty -six thousand miles a second. Dr. Curtis thinks these new stars may possibly have been of the thirtieth magnitude before their outburst, and so as far distant as 20,000,000 light years. He believes that the smaller spiral nebulae are ten to a hundred times more remote than the nebulae of ten minutes of arc in the heavens, which would havo an actual diameter of nearly 60,000 light years. Dr. Curtis Cur-tis suggests the possibility that there may be absorbing material in the spiral nebulae which would reduce the apparent ap-parent brightness of these two stars and thus make them seem farther away than they really are. However, In discussing the difference between the new stars which have been discovered ' in our own galaxy, which on the aver-, aver-, age are of the fifth and a half magni-j magni-j tude, and the three new stars which he i has now discovered in spiral nebulae, ( he points out that the six new stars' discovered in spiral nebulae are on the , average ten magnitudes fainter, and j therefore a hundred times as far away j as the average of. the twenty-six new i stars which have been recorded in the Milky Way. This is evidence that the spiral ne-, ne-, bulae are far outside our own stellar : system, each constituting o itself a I whole universe of suns, comparable in j vastness with our own Milky Way. |