Chapter 27: The Milky Way

On the Milky Way.⁸²⁹

1 ⟨Aëtius⟩: The milky circle

It is a cloud-like circle, continually visible in the air and called the Milky Way because of its white color.

2 ⟨Aëtius⟩: A fiery track

Some Pythagoreans said that it is the scorching caused by a star which fell from its own station and burned in a circle the region through which it ran, at the time of the conflagration associated with Phaethon. Others say that the sun originally followed this course.⁸³⁰

2 ⟨Aëtius⟩: Reflection

Others held that it is a mirror-like appearance produced by the sun reflecting its rays toward the heavens, just as happens with the rainbow on the clouds.⁸³¹

3 ⟨Aëtius⟩: Metrodorus

Metrodorus held that it is due to the sun’s passage, for this is the sun’s circle.⁸³²

4 ⟨Aëtius⟩: Parmenides

Parmenides held that the mixture of the dense and the rarefied produced a milk-like color.⁸³³

5 ⟨Aëtius⟩: Anaxagoras

Anaxagoras held that the earth’s shadow occupies this part of the heavens when the sun, having passed beneath the earth, does not illuminate everything.⁸³⁴

6 ⟨Aëtius⟩: ⟨Democritus⟩

⟨Democritus⟩ held that it is the combined radiance of many small, closely gathered stars, illuminating one another because of their density.⁸³⁵

7 ⟨Aëtius⟩: Aristotle

Aristotle held that it is the ignition of a dry exhalation, abundant and continuous.⁸³⁶

7 ⟨Arius Didymus⟩: The star-filled circle

For the circle in which it seems to appear is a great circle, full of the largest and brightest stars, as well as those called “scattered.” Because of these, a very great quantity of exhalation from the earth continually gathers about this region and produces the appearance of the Milky Way.⁸³⁷

8 ⟨Aëtius⟩: Posidonius

Posidonius held that it is a formation of fire, more rarefied than a star but denser than a ray of light.⁸³⁸