Bookcase A includes: the Universe (beginning, mysteries, evolution, future), cosmology, dark matter, and more.

Bookcase B includes: Large scale structure, galaxies, stars, stellar evolution, variable stars, supernovae, black holes, and multiwavelength astronomy.

Bookcase C includes: books about the cosmos and science.

Bookcase E includes: books on individual bodies in the solar system (sun + planets + minor bodies like comets, asteroids, and meteors).

Bookcase F includes: quantum mechanics, relativity, time, general pop-sci astronomy books, and multicultural astronomy books.

Bookcase G includes: educational texts for science, science teachers, intro astronomy, intro physics, and cosmology.

Bookcase H includes: uncorrected proofs and popular mainstream science books/authors.

Bookcase J includes: Earth, Earth Science, the Moon, history of humans and the cosmos, philosophy of science/astronomy, and life outside our solar system.

Bookcase K includes: SETI, extraterrestrial life, history of telescopes and observatories, and modern observatories.

Bookcase L includes: biographies, women in science, and history of astronomy.

Bookcase M includes: anything to do with human and robotic space exploration, some aviation topics as well.

Bookcase N includes: solar ephemerides, solar eclipse, planetary and solar system studies, and planetary ephemerides.

Bookcase P includes: general stargazing, the night sky, amateur astronomers, deep sky objects, and operating and/or building your own telescope.

Bookcase R includes: computers/calculations in astronomy, observational astronomy, astrophotography, optics, orbital mechanics, and celestial mechanics.

Bookcase S includes: graduate level texts on stars, stellar atmospheres, particle physics, and astrophysics.

Large format books range from coffee table photo books about astronomy, space, and space exploration to historical atlases.

Windowsill books include: large sky atlases, amateur astronomy, backyard astronomy, etc.