Astronomy is the study of everything in the universe beyond Earth's atmosphere. That includes objects we can see with our naked eyes, like the Sun , the Moon , the planets, and the stars . It also includes objects we can only see with telescopes or other instruments, like faraway galaxies and tiny particles.

As the name goes by, linear algebra is the study of straight lines involving linear equations. Calculus is about understanding smoothly changing things involving derivatives, integrals, vectors, matrices, and parametric curves, etc.