• Journal of Astronomy and Space Sciences
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• v.21 no.1
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• pp.39-72
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• 2004

We present a more complete and accurate catalogue of astronomical records far meteor showers and meteor storms appeared in primary official Korean history books, such as Samguk-sagi, Koryo-sa, Seungjeongwon-ilgi, and Chosen-Wangjo-Sillok. So far the catalogue made by Imoto and Hasegawa in 1958 has been widely used in the international astryonomical society. The catalogue is based on a report by Sekiguchi in 1917 that is mainly based on secondary history books. We observed that the catalogue has a number of errors in either dates or sources of the records. We have thoroughly checked the primary official history books, instead of the secondary ones, in order to make a corrected and extended catalogue. The catalogue contains 25 records of meteor storms, four records of intense meteor-showers, and five records of usual showers in Korean history. We also find that some of those records seem to correspond to some presently active meteor showers such as the Leonids, the Perseids, and the n -Aquarids-Orionids pair. However, a large number of those records do not correspond to suck present showers. This catalogue we obtained can be useful for various astrophysical studies in the future.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.283-298
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• 2003

The 2001 Leonid meteor storm has been observed all over the world, and its most intense flux since the last few decades has caused great interest among both laymen and experts. Especially, its maximum hours occurred at dawn hours of Nov. 19 in the east Asia, during which moonless clear night at the Mt. Bohyun allowed us near perfect condition of observation. Observation was carried out in the period of 01:00∼05:40(KST), which include the predicted maximum hours, with all-sky camera installed for upper atmospheric airglow research. Tn this paper we analyze 68 all-sky images obtained in this period, which contain records of 172 meteors. Utilizing the zenith hourly rate(ZHR) of 3000 and magnitude distribution index of 2, which were reported to International Meteor Organization by visible observers in the east Asia, we estimate the limiting magnitude of about 3 for meteors detected in our all-sky images. We then derive magnitudes of 83 meteors with clear pixel brightness outlines among the initially detected 172 meteors by comparing with neighbor standard stars. Angular velocities of meteors needed for computing their passing times over an all-sky image are expressed with a simple formula of an angle between a meteor head and the Leonid radiant point. The derived magnitudes of 83 meteors are in the range of -6∼-1 magnitude, and its distribution shows a maximum new -3mag. The derived magnitudes are much smaller than the limiting magnitude inferred from the comparison with the result of naked-eye observations. The difference may be due to the characteristic difference between nearly instantaneuous naked-eye observations and CCD observations with a long exposure. We redetermine magnitudes of the meteors by adjusting a meteor lasting time to be consistent with the naked-eye observations. The relative distribution of the redetermined magnitudes, which has a maximum at 0 mag., resembles that of the magnitudes determined with the in-principle method. The relative distribution is quite different from ones that decrease monotonically with decreasing magnitudes for meteors(1∼6) sensitive to naked-eye observations. We conclude from the magnitude distribution of our all-sky observation that meteors brighter than about 0 mag., appeared more frequently during the 2001 Leonid maximum hours. The frequent appearance of bright meteors has significantly important implication for meteor research. We noted, however, considerably large uncertainties in magnitudes determined only by comparing standard stars due to the unknown lasting time of meteors and the non-linear sensitivity of all-sky camera.

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.529-552
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• 2004

We made a robust catalogue of reliable records of meteor showers and storms recorded in Korean, Japanese, and Chinese chronicles. In our new catalogue, there are 35 Korean records, 29 Japanese records, and 93 Chinese records. The temporal frequency distribution of records shows two broad peaks around the 10th and the 16th centuries. We observed that the peak in the 10th century is mainly contributed by the Perseids, while the peak in the 16th century was mainly contributed by the Leonids. We found that the ${\eta}-Aquarids$, the Perseids, the Orionids, and the Leonids have been active during the last two millennia. The oldest record of the ${\eta}-Aquarids$ is that of BC 687 in China, and the oldest record of the Perseids is that of 36 AD. Contrary to previous investigations, there has been no nodal shift of the ${\eta}-Aquarids$ and the Orionids, whose mother comet is the Halley's comet. The oldest record of the Leonids is probably that of 288 AD, instead of 902 AD. We also find some evidence on the existence of a possible shower a-Draconids. We note that our catalogue will be useful to investigate meteor showers.