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

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and s and m the angular semidiameters of the Sun and
the Moon. (This formnla we shall see later). This higher
limit comes to 88.5'. The limit of 56' for the occurence
of a lunar eclipse is the value of
pm + ps — s + m as we shall see later.
The latitude of 56' of the Moon arises out of a longi-
tude of 12° of the Moon with respect to a node, whereas
the latitude of 32' arises out of a longitude of 7° with
respect to the node. Since at an eclipse solar or lunar,
the longitude of the Moon with respect to a node, is the
same as the longitude of the Sun with respect to the same
or opposite node, the latter must be 12° for the occurence
of a lunar eclipse. But as the difference between the
mean and true Suns is about 2°, the longitude is stipulated
as 14°. In other words, for the occurence of a lunar
eclipse, the longitude of the Sun on the full-Moon day
with respect to the nearer node shall be less than 14°. To
compute this longitude of the Sun with respect to the
nearer node on a full-Moon day, we are given the subse-
quent procedure indicated in the verse. In 53433500000
lunations of the Kalpa, the sum of the sidereal revolutions
of the Sun and the Node (Rāhu) (Sum because Rāhu has
a retrograde motion) is equal to 455231168 which is equal
to 455231168 × 12 = 54627734016 Rasis. Then in one
lunation what will be the increase of the longitude with
respect to the Node? The result is
54627734016 / 53433300000 = 1 Rasi + 3583302048° / 5343330000 (= 74652126 / 111319375)
dividing by 48 both the numerator and denominator.
Taking the first two digits in the numerator and denomi-
nator of the fraction the fraction is approximately equal
to 74/111 or 2/3. Taking this as a convergent we make
amends for the roughness as follows.
74652126 / 111319375 = 2/3 (1 + 1/λ) ∴ λ = (2 × 111319375) / (3 × 74652126 — 2 × 111319375)