本帖最後由 WCYue 於 2023-7-18 11:14 編輯
2024年土星衛星互相掩食現象
Mutual eclipses and occultations of satellites
This module computes predictions of mutual eclipses and occultations of the major satellites of Jupiter, Saturn, and Uranus. Eclipses occur in a well-defined period as the sun passes through the orbital plane of the satellites. However, the Earth passes through the orbital plane either once, or three times, at each apparition. As a result, occultations can occur either over an extended period.
For satellites whose orbits are close to co-planar, eclipses and occultations occur when the Sun or Earth passes through the orbital plane. When the orbital planes are not close to being co-planar, mutual events only occur when the respective satellites are at the location of the node of the apparent orbits. There are two such satellites:
Iapetus (Saturn). The orbit is inclined 15 deg. to the orbits of the other satellites. Its orbit is outside the orbits of the other satellites. The result is that eclipses and occultations do not occur when the Earth/Sun passes through the orbital plane of the other satellites, but several years removed. The number of eclipses and occultations that occur during such an apparition is quite small. In the 2006/7 apparition, there is one such event - on 2007 Jan 6, Iapetus occults Mimas. To make sure events are found, specify a large minimum separation, such as 4”.
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發表於 2023-7-18 11:11:41