Korean nova records in A.D. 1073 and A.D. 1074: R Aquarii
Korea Astronomy and Space Science Institute, 61-1 Hwaam, Yuseong, Daejeon 305-348, Korea e-mail: [hjyang;cho]@kasi.re.kr
2 Department of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu 702-701, Korea e-mail: email@example.com
3 School of Physics, Korea Institute for Advanced Study, Seoul 130-722, Korea e-mail: firstname.lastname@example.org
Accepted: 31 December 2004
R Aqr is known to be a symbiotic binary system with an associated extended emission nebula, possibly produced by a historic outburst. To find the associated historic records, we searched for and compiled all Guest Star and Peculiar Star records in three Korean official history books that cover almost two thousand years, Samguksagi, Goryeosa, Joseonwangjosillok. In addition to the record of A.D. 1073, previously noted by Li (1985, Chin. Astron. Astrophys., 9, 322), we have found in Goryeosa another candidate record of A.D. 1074, which has the same positional description as that of A.D. 1073 with an additional brightness description. We examined various aspects of the two records and conclude that they both are likely to be the records of outburst of R Aqr. This means that there were two successive outbursts in A.D. 1073 and in A.D. 1074, separated by approximately one year. Based on these records, we estimate the distance to R Aqr to be 273 pc if the expansion of the nebula has been at a constant rate. The brightness record of A.D. 1074 corresponds to the absolute magnitude at outburst of ~ at this distance. The two Korean records associated with R Aqr may provide astronomically meaningful constraints to the outburst model of R Aqr and the formative process of its nebulosity.
Key words: stars: binaries: symbiotic / ISM: planetary nebulae: general / history and philosophy of astronomy
© ESO, 2005