Currently these notes cover: a brief overview of astronomy's place in the
scientific endeavor, the philosophy of science and the scientific method,
astronomy that can be done without a telescope, a history of astronomy and
science, Newton's law of gravity and applications to orbits, Einstein's Relativity
theories, electromagnetic radiation, telescopes, all the objects of the solar
system, solar system formation, determining properties of the stars, the Sun,
fusion reactions, stellar structure, stellar evolution, the interstellar medium, the
structure of the Milky Way galaxy, extra-galactic astronomy including active
galaxies and quasars, cosmology, and extra-terrestrial life. This site also has
pages giving angular momentum examples, a quick mathematics review,
improving study skills, astronomy tables, and astronomy terms.
All of the line drawings were done with Create on my old NeXT machine or
with Freehand on a wintel laptop and Macintosh at home. The line art images
on the screen are GIF and PNG images. If you have comments about these
notes, please email me.
Plenty of updates made to most of the chapters, especially the
asteroid/comet/exoplanets, other galaxies, cosmology, and extra-terrestrial
life chapters as part of updating the hardcopy edition that came out in the
summer of 2013. The website is continually updated.
Contents (chapters + descriptions):
1. Astronomy as a Science and a Sense of Scale. I introduce astronomy's
place in science, and give a sense of the size and time scales involved.
Also discussion of the scientific method and how astrology is not a
science and what makes astronomy a science.
A separate section about the Science-Religion interface and interaction is
available on this site. It is not part of the regular textbook. I take a
middle road between the fundamentalists on both sides of the
2. Method for Finding Scientific Truth. Borrowing from Pine's book
``Science and the Human Prospect'' I discuss the scientific method,
correlations, problem of induction, positivism, levels of testimony,
empiricism, models correspondence with reality.
Pseudoscience vs. science article. Borrowing from Carl Sagan's "The
Demon-Haunted World", I take up the subject of UFOs as alien
spacecraft. This article is not part of the regular textbook.
3. Astronomy Without a Telescope. I discuss the celestial sphere, motions
of the Sun (solar and sidereal days, time zones, equation of time, and
seasons), motions of the Moon (phases and eclipses, including my own
pictures of some solar eclipses), and planetary motions. 4. History of Astronomy. I focus on the rise of modern science in Europe,
from the ancient Greeks to Kepler.
5. Newton's Law of Gravity. Newton's laws of motion and his law of
gravity are discussed. Applications of those laws (esp. gravity) are
covered (e.g., measuring the masses of planets and stars, orbital motion,
interplanetary trips, tides, etc.).
6. Einstein's Relativity. I discuss Einstein's Special Relativity and General
Relativity theories. The concepts of spacetime and gravity as a warping
of spacetime are introduced along with observational proofs of his
theories, including the search for gravity waves with LIGO.
7. Electromagnetic Radiation (Light). General properties of light, definition
of frequency, spectrum, temperature. Light production: Continuous
(thermal) spectra, emission lines, absorption lines and the Bohr model
for the atom. Doppler Effect and why spectral lines must be used to
measure the doppler shifts.
8. Telescopes. Covers refractors, reflectors, radio telescopes, light-
gathering power, resolving power, interferometers, magnification, and
atmospheric distortion such as seeing, reddening, and extinction.
9. Planetary Science. This chapter is an introduction to planetary science. I
discuss the techniques astronomers use to find out about the planets,
their atmospheres (what determines if an atmosphere sticks around;
behavior of gases; what determines the surface temperature; atmosphere
layers; the transport of energy; effects of clouds, mountains, and oceans;
weather vs. climate and climate change agents with feedbacks; and
appearance), their magnetic fields (the magnetic dynamo theory), and
their interiors including the geological forces at work reshaping their
surfaces. In a separate section I focus on a comparison between the
atmospheres of Earth, Venus, and Mars and why they are now so
radically different from each other (greenhouse effect, carbon cycle,
runaway refrigerator, runaway greenhouse, etc.) Mars discussion now
includes proofs for liquid water in past and sub-surface water ice. The