Book 2 · Foundations

The science of stars, planets, and space.

In addition to; as well as.

A bowl-shaped hole, often where a meteor hit or a volcano opens.

One step in a series — used for temperature, angle, or rank.

The length of a straight line across a circle through its centre.

A long steady look; to look long and steadily.

The pull that draws things toward Earth (or any large body).

To throw back light or sound; to think carefully.

A tube with lenses for seeing far-away things up close.

All of space and everything in it.