# 1. Space, Time, Matter, & Energy

### Joshua Barnes -- Fall 1999

The first week of this course is an introduction to some of the
things we find in the Universe -- atoms, light, planets, stars, and
galaxies. These lectures also describe a useful way of comparing
the sizes, ages, and masses of different astronomical objects.

**Topics:**

- Linear & geometric scales
- Scientific notation (see App. A)
- The size of the Universe (see Intro)
- Cosmic time
- Atomic structure (see Ch. 4-1)
- Light & radiation (see Ch. 3-1)

**Video:** *Powers of Ten*

**Web Resources:**

- Scientific Notation
A brief primer on scientific notation, and an on-line test
you can take to check your understanding.

- Just What is a Logarithm, Anyway?
A readable explanation of linear and geometric scales (also
known as logarithmic scales) as well as an introduction to
logarithms. (Note: available as a PDF file only.)

**Homework 1:** *The Sun & You*,
due 8/30. Answer.

**Quiz 1:** *An Alien Clue?*

Joshua E. Barnes
(barnes@ifa.hawaii.edu)
Last modified: September 3, 1999

`http://www.ifa.hawaii.edu/~barnes/ast110_99/stme.html`