Iye Masanori, Ito Takashi
National Astronomical Observatory of Japan, Mitaka, Tokyo, Japan.
PERC, Chiba Institute of Technology, Narashino, Chiba, Japan.
Proc Jpn Acad Ser B Phys Biol Sci. 2025;101(3):143-176. doi: 10.2183/pjab.101.012.
In 1962, Yoshihide Kozai reported his findings on the secular dynamics of asteroids moving in orbits with high inclination and eccentricity. In contrast to the classic understanding of the stability of planetary motion in the solar system, Kozai showed that asteroids can significantly change their orbital shape over a long timescale in an oscillatory manner between nearly circular orbits and highly elliptic orbits. An anti-correlated variation between orbital inclination and eccentricity characterizes this oscillation. The importance of Kozai's work in understanding the dynamical evolution of various systems was recognized decades later, including the fields of irregular satellites of planets, Oort Cloud, extrasolar planets, binary star systems, type Ia supernovae, planet climate, merging black hole systems, and so on.
1962年，小柴义秀报告了他对在高倾角和偏心率轨道上运行的小行星长期动力学的研究结果。与对太阳系中行星运动稳定性的传统理解不同，小柴表明，小行星可以在很长的时间尺度上以振荡的方式在近圆形轨道和高度椭圆轨道之间显著改变其轨道形状。这种振荡的特征是轨道倾角和偏心率之间呈反相关变化。几十年后，小柴的工作在理解各种系统的动力学演化中的重要性得到了认可，这些系统包括行星的不规则卫星、奥尔特云、系外行星、双星系统、Ia型超新星、行星气候、合并黑洞系统等等。
