सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

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Vikṣepa or the celestial latitude of the Moon M₂ R₂ is to
be drawn along this Valanasūtra M₂ V. With R₂ as centre
and radius p drawn the Rāhu-Bimba.
Fig. 89 Depiction of Fig. 88, keeping the Moon fixed
The slight flaw in this figure is that ML₁ L₃ implied
as the path of the Moon is taken to be parallel to the
ecliptic R₁ R₂ R₃ the path of the eclipsing body the
Grāhakamārga, in as much as latitudes are drawn perpendi-
cular to ML₁ L₃.
This figure depicts a total eclipse of the Moon. If M
coincides with R₂ at the middle moment of the eclipse,
then the eclipse is called central.
The duration of a central eclipse will be on the
average the time that the Moon's disc takes to cross the
diameter of the Rāhu-Bimba with its relative velocity.
Hence the mean duration of a central eclipse is
Average diameter of Rāhu + Average diameter of the Moon
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Relative velocity of the Moon with respect to the shadow
= [(81+64) × 24] / [790′-35″ — 59′-8″] hrs = 145/732 × 24 = 290/61 =
4 hrs–45 minutes approximately.