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SN1987A (LMC)

+4

Chinese (Hou Han-shu, T'ung-k'ao) Optical;radio

Chinese (T'ung-chih, T'ung-k'ao). Radio, x-ray;pulsar Chinese (Chin-shu, T'ung-chih, T'ung-k'ao). Possible radio Chinese (Yü-hu ch'ing-hua, T'ung-k'ao, Sung-shih); Japanese

(Meigetsu-ki); European (Hepidanus;Barhebraeus). Optical, x-ray, radio

Chinese (Sung-shih); Japanese (Meigetsu-ki); North America? (Fern

Cave;Chaco Canyon)—see text. Optical, x-ray, radio;pulsar Chinese (Sung-shih, T'ung-k'ao, Chin-shih); Japanese (Azumakagani,

Gyokuyo, Meigetsu-ki, Hyakuren-sho). Optical, radio Chinese (biography of Shen-tsung from Ming-shih, preface of Ming Ting-wen) European (Tycho Brahe);Korean. Optical, x-ray, radio Chinese (Ming-shih, T'ung-k'ao) European (J. Kepler). Korean (Sonjo

Sillok). Optical, radio Modern Modern against the Aristotelian view of the heavens as changeless and perfect. It was not, however, the first such event to be witnessed and recorded in human history.

The best-known supernova remnant is the Crab Nebula— a product of the supernova of July 1054. This particular supernova will be discussed further in §13.1 under North American astronomical representations, because there is evidence for its depiction on the roof of a rock shelter in Chaco Canyon, New Mexico (see Figure 13.1), and at least one other site, Fern Cave, California. A Mimbres pot from New Mexico may bear another representation (§13.1). Among the known extant records of supernovae in far Eastern annals are those of 1006, 1054, 1572, and 1604. All but the 1054 SN were noted in Western Europe; of the 1054 SN, however, there is no obvious trace (see §5.8.6 below, however, for a reevaluation). The identification of the 1054 SN in Chinese records indicate that it was as bright as Venus (Needham/Ronan 1981, p. 205). The expanding gas cloud that was the star's envelope—the Crab Nebula—is still visible, and from its angular size and rate of expansion, its age can be determined, assuming that the expansion velocity has been constant. This assumption is not exactly right, but the resulting age is in reasonable agreement with the date of the records (there are actually five records of it). The guest star was reported as having disappeared in April 1056. This "guest star" appears on the Su Chow (or Suzhou) star chart (Figure 10.7) from Sung Dynasty, China, ~1193 a.d. (see §10.1.2.3, and §10.1.7 for context). The text from the Sung Hui Yao, "History of the Administrative Statutes of the Sung Dynasty," is interesting for at least two reason: It mentions the color of the star, and it throws light on the motivation for performing this kind of work:

In the fifth month of the first year of the Chih-Ho reign period, Yang Wei-Te (Chief Calendar Computer) said, 'Prostrating myself, I have observed the appearance of a guest star; on the star there was a slightly iridescent yellow color. Respectfully, according to the disposition for emperors, I have prognosticated, and the result said, 'The Guest star does not infringe upon Aldebaran; this shows that a Plentiful One is Lord, and that the country has a Great Worthy.' I request that this prognostication be given to the Bureau of Historiography to be preserved. (Needham/Ronan 1981, p. 207)

The yellowish color mentioned in the text is the eye's response to a star that has a strong red component to its color; as observational astronomers can attest, "yellowish" is an appropriate color description of even M spectral class red stars as viewed from dark, mountain-top sites. In the case of the nova, an important source of the red component is the very strong emission line radiation at 656.3 nm (the principal line of the Balmer series, Ha, of atomic hydrogen).

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