* Astronomy

Title: The Pantar, Lanao, Philippine Islands, Meteorite
Authors: H. H. Nininger

A 2,320-gram aerolite which was observed to fall on June 16, 1938, at Pantar, Lanao, Philippine Islands, by Mr. R. H. Wygle, is described as being of the ordinary chondritic variety. Mr. Wygle was extremely fortunate also in securing a photograph (herewith reproduced) of the dust cloud which appeared in the wake of the meteorite. There was a press report to the effect that, at the time of the fall of the meteorite, many small particles fell like rain onto the metal roofs of several houses. There is no reason to doubt this report, for a similar occurrence has been recorded in connection with at least four North-American falls. That this phenomenon is in some way related to meteoritic clouds is reasonable to assume. If the connection is established, then ordinary meteoritic showers will have to be reckoned, probably in tons, instead of grams, of material!
The fall of the Pantar, Lanao, Philippine Islands, meteorite was first reported to the writer through Professor F. M. Van Tuyl of the Colorado School of Mines. His information came from Mr. R. H. Wygle of Cagayan, Misamis Or., Philippine Islands, who not only was an eyewitness to the event, but also made a valuable contribution to the science of meteoritics by photographing the dust cloud which appeared in the wake of the meteorite. The fall is said to have taken place on June 16, 1938. The hour of arrival was not stated, but it took place presumably in daylight hours, since the account states that one stone was seen to land in a rice field and was later extracted from a depth of one meter. Its weight was given as 2,320 grams. Mr. H. J. Detrick was responsible for its preservation and for delivering it to the Governor of Lanao.

A small specimen weighing 16.8 grams has been examined by the writer and has been found to be of the ordinary chondritic variety. The interior is of a grey colour except where stained brown from the incipient oxidation of some of the nickel-iron grains which are very abundant in the stony matrix. The chondrules, which constitute a large part of the stony matrix, are small in size, rarely more than one mm. in diameter in the specimen examined. The matrix appears to be a breccia of two different materials which differ only slightly in colour-one a darker grey than the other. In the darker member the chondrules break with the matrix, while, in the lighter-coloured one, they survive the breaking of the mass. Dark, thin veins permeate the stone in several places. The nickel-iron grains are plentiful and are of about the same average size as those in the Beardsley, Kansas, fall of 1929. They are extremely irregular in form. Sulphide grains are small and not very numerous in the specimen examined. The specimen at hand is covered by the usual dull, brownish-black fusion crust, which is scarcely more than one-tenth of a mm. in thickness.
Two very important things have been secured in connection with this fall. The first is the photograph of the dust cloud obtained and delivered by Mr. Wygle. This photograph is herewith reproduced. Discussion of the apparently vaporous clouds surrounding the meteoritic cloud must await a more detailed report by Mr. Wygle. If these are vapour clouds, then the meteoritic cloud must have been very distinct indeed to show so clearly through them. Meteoritic clouds are not known to develop lower than about seven or eight miles. The distance of this cloud from the photographer was not reported, but Mr. Wygle did report that the sound of "a series of explosions" arrived about sixty seconds after the flash of the meteor. He also described the smoke as being of an old-rose colour. Such photographs as this one (made apparently with an ordinary kodak) are very rare, and yet they are extremely important in the science of meteoritics. It is hoped that more will be made as falls take place in the future.
Second, a very important fact recorded in connection with the Pantar fall is taken from the press reports and has not yet been verified, but there is no reason for doubting its occurrence, since at least four other similar cases have been cited for North-American falls. This is the report that small particles fell like rain onto the metal roofs of several houses. It is hoped that this report may later be verified and that the extent of this shower also may be determined. The writer has several times expressed his belief that this kind of phenomenon is the most important of all of those to be investigated in connection with meteoritic falls. That it is related to meteoritic clouds is reasonable to assume. If this relation is proved to exist, and if the extent of the phenomenon is discovered to be comparable to the dimensions of these clouds, then ordinary meteoritic showers will have to be thought of eventually in terms of to11s instead of grams of material'
A photograph taken, apparently through atmospheric clouds, by R. H. Wygle about a minute after the meteor caused by the Pantar meteorite appeared.

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