Determination of Preliminary Orbital Elements of the Great Comet C/1665 in Korean History

Study on the system of night hours for decoding Korean astronomical records of 1625–1787

“…Therefore, we think that the system of night hours by Naepyeon and not by Shixianli has to be used for estimating the observation time for Korean astronomical records before 1719. For this reason, the calendrical method of Naepyeon has to be used to estimate observation time for the comet that appeared in the fifth reign of King Hyeonjong, 1665, as did by Ahn et al (2006). However, Park (1982) (originally Yamamura, 1932) used the calendrical method of Shixianli.…”

Korean Historical Records on Halley's Comet Revisited

“…Compared with the orbital path derived from the orbital elements of Yeomans & Kiang (1981), the latter value gives a smaller difference than the former one if the reference star of the first lunar mansion is Vir (Ahn et al 2006, Cullen 2007. On the other hand, both history books talk about the observers of the comet at that time: Do-Il Oh, Yeong Im, SeGi Yoon, Du-Myeong Kim, and Im-Il Mok.…”

Structure and Conceptual Design of a Water-Hammering-Type Honsang for Restoration

“…Divided by 3 Bun, 10 Cheok 9 Chon 6 Bun corresponds to approximately 365.33 which is almost the same as the length of one year and can be represented using the scale of 365.2575. With this value, the diameter of Honsang would be approximately 72.2 cm.4 In Gukjoyeoksanggo and Seowoongwanji from the latter part of the Joseon dynasty, the descriptions on the scale of Jeokdokyeongeuiui (赤道經緯儀) determined the range by the 5 Do scale limit and the 10 Do scale limit.5 The expression of Yak (弱) is interpreted as an addition of 11/12 to 24 Do or as a subtraction of 1/12 from 24 Do Ahn et al (2006). argue for the latter opinion, and this results in approximately 23.91 Do.…”