59r

The Moon

¶ The moon is the closest of all the planets
and it finishes its day very late.
Its sphere is transparent and diaphanous,
as are the others,^{1ie. the spheres of the other planets} the view of which is unobstructed.
And so, you will not be looking in vain
all the way up to the fixed stars ^{2this is the translation of the celestial sphere}
because you can take pleasure in gazing up at those
bright planets and shining stars.

Obscuring of the Sun

However its body—I speak of the moon—
is solid, dense, and not transparent.
And therefore, when it interposes itself anywhere
along a straight and even line between the sun and us,
it appears dark to us, blocking [the sun's] rays
and does not allow them to pass through to us.
When this eclipse [>>"eclissi"] is completed
is the point when it [the moon] changes from old to new.^{3It is unclear why Dati connects the solar eclipse to the phases of the moon, as in the next stanza}

Phases of the Moon

¶ Without light of its own, the amount [of the moon] that is dark changes,
so that it is illuminated according to how much it faces the sun.
For this reason, its shape is variable
because it shines halfway between what is above and below [the sun and the earth].
As the distance between it and the sun increases
each day, it casts more light
onto the earth: and then when it returns and gets closer
each day, the light from it wanes.