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Show ON METEORIC SHOWERS. THEIR VISITS OF FREQUENT PERIODICAL PERI-ODICAL OCCURRENCE. Pecultaritiea of tha IleaYenly Displays. New Feature of tha Sun Remain! to tha Aatronomen A Talk With, a Frofaaaor on a Sky Hlh Subject. In answer to several questions regarding regard-ing the. frequency of meteoric showers Professor Very 6aiil: "TUero are certain epochs in the year when particular meteoric showers are due. - Assiduous observation has given a list of nearly 100 such showers in the course of a year, each of which may be expected on a certain data from a certain part of the heavens. "Particular showers havo characteristic characteris-tic features; that is, some meteors are very swift: others rather slow-. Some vanish and leave no trace, while other are accompanied by tails and leavt streaks after the nucleus has disappeared. disap-peared. Few of these showers last mor than one or two days, though there are some instances where ii is suspected that successive meteors belonging to the same group appear during several weeks. Certain Cer-tain dates have been noticed to be more especially fireball epochs. That is, the rare event of an exceptionally large and brilliant meteor or fireball it more apt to occur on certain dates. "Jan. 25 is the date of the meteoric shower characterized by the swiftness of its components, which are usually at- tended by streaks. The radiant point of this shower is in the constellation called Bernice's Hair, a star cluster oue of the morning constellations. As this meteor is claimed to havo been seen in the even ing it is more likely to have been one of the unclassified sporadic meteors. Information Infor-mation as to the position of motion, apparent ap-parent brilliancy, color, time of appearance appear-ance and length of time duriujr, which the appearance lasted is likely to be valuable valu-able in the recovery of the principal characterist ics of an event which is necessarily neces-sarily seen but by few." - "How do you account for these meteoric mete-oric showers coming at regular periods?" was asked. "All that we can say is that the celestial celes-tial spaces are thinly populated in every direction with these scattered f raj;niont8, which axe veritable miniature planets traveling in different orbits around the sun in many instances, and serving as messengers from one star to another in others. " "The number of them is simply countless. count-less. They make up in number what tbey lack in 6ize, so that if we could gather together all the minute members that go to make up a group it might make a body of very respectable size, although al-though the individual components are so small that they seldom escape completo disintegration and dissolution in their passage through the atmosphere." "What produces the great light which always follows the passage of a meteor?" "The light which is seen while the passage pas-sage of a meteor through the air lasla may be due partly to tha combustion of the materials of the air of life, but it k mainly an incandescence of the condensed condens-ed atmosphere which accumulates in advance ad-vance of an object which is moving many times the rapidity of a cannon bull often, I may say, with many hundred times the rapidity of a cannon ball Under Un-der these conditions even the seemingly flimsy resistance of the air becomes aa great as that of a solid body, producing intense heat, and in the case of a large meteoric stone frequently resulting in the fracture and demolition of the object. "Colored meteors are sometimes seen with a peculiar tint of Jthe flame, being due to the burning of some special ingredient ingre-dient of the meteor. We have yellow, green and occasionally red meteors, but tho majority are white like the majority of the stars. It cannot be said that any one part of the earth can be more affected affect-ed by these visitants than another. There is, however, a diurnal periodicity, the larger numbers being seen in the early morning hours when that portion of the heavens comes in view toward which the the orbital motion of the earth is carrying carry-ing us. We then see not merely the comparatively com-paratively few meteors whose speed is sufficient to enable them to overtake the earth, but that larger number composed of all those which are gathered up iu the track of the advancing earth, whether moving with against or athwart its course." "The appearance of the oollected results re-sults of the observation of tho total eclipse of Jan. 1, 1889, shows that this event has added many interesting facta to tho previous pre-vious knowledge of such occurrences. A large and very perfect photograph of the corona was obtained by Professor William II. Pickering, of Cambridge, Mass., and one of a smaller size by Professor Pro-fessor Barnard, of tho Lick observatory. "These show the sheaves of curling fragments about the sun's poles in great detail, indicating the composite natura of many of the individual iilaments, and confirming the photographs taken at the previous win spot minimum of 187ti, thus rendering it almost certain that tlio corona at this period assumes a symmetrical symmet-rical form with regularly disposed lila-uients lila-uients curving away on either side of the sun's axis and broad equatorial wiagl of less discriminated etrncture. "AU this is very different from what is seen during an eclipse when the activity ac-tivity of the sun is in its height. At such times the corona hag a rudely quadrilateral quadrila-teral outline, with four wir.gn projecting from regions approximately 4U dK. north and south of the equator, and the whole is made up of curved branching and interlacing BtrcanK-M extending w a much greater distance from the body of the sun, and with tho equatorial sheaves less, symmetrically diBOsed. In regard to the extent of the corona, it is diflicult to compare successive eclipses observed from different part3 of tue earth with verv varying atmospheric condition. A small amount of haze will blot out uiucii of the fainter detail. The presence r absence of some of theso fainter features may merely signify the. presence or absence ab-sence of tin couduion of their ot,f-rva-tion, but the variation of type in a tiiia beyond question. We wem to have a connection indicated between the brod equatorial winzs a:: J the sua spot ioces." I'lttoburii Di. paieb. |
