Astronomy

The Quadrivium:
[4] Arithmetic, [5] Geometry, [6] Music, and [7] Astronomy.

The Quadrivium (which pertains to Matter & Quantity)- the advanced four.

[7] ASTRONOMY —Number in space and time.
a. Number
b. Geometry
c. Harmonics
d. Cosmology

The Quadrivium with Gene Odening, Gnostic Media Podcast episode #050 (start here)

Quadrivium – Number, Geometry, Music, & Cosmology with John Martineau, Gnostic Media Podcast episode #103 (intermediate)