Introduction to Astrophysics

Astrophysics is the study of the physics of the universe. Various objects, such as stars, planets, and galaxies, are studied under the scope of astrophysics. Since astrophysics is a very broad subject, many disciplines of physics are typically applied.

Historical context

 * 1) Early Views
 * 2) Aristotle
 * 3) /Nicolas Copernicus/
 * 4) /Galileo/
 * 5) Johannes Kepler
 * 6) Isaac Newton
 * 7) /Albert Einstein/
 * 8) /Stephen Hawking/

Basics

 * 1) Stellar Luminosity
 * 2) Stellar Classification
 * 3) Hertzsprung&#x2010;Russell Diagram

Stellar Types
Real Hypothetical
 * 1) /Light Stars/
 * 2) /Heavy Stars/
 * 3) /Main Sequence Stars/
 * 4) /Red Giants/
 * 5) /White Dwarfs/
 * 6) /Black holes/
 * 7) /Neutron Stars/

The science of Astronomy relies on universality of Physical laws. "Same in the heavens as on earth". The world of stellar objects presents us with stupendously larger scales of agglomeration of matter and energy, at which to apply the known laws. Thus we are led to new predictions of entities that have never been observed before. Likewise some species of elementary particles and certain states of matter never observed on Earth need to be postulated in order to accord with observations. Some objects and phenomena falling in such categories and awaiting confirmation or further observational details are in this list. Eventually we expect them to be confirmed in all detail. If they contradict our predictions or conflict with phenomena known on Earth, well that would be even more exciting because that would be a new discovery awaiting explanation.
 * 1) /Black Dwarfs/
 * 2) /Quark Stars/
 * 3) /Protostars/
 * 4) /Dark Matter/
 * 5) /Dark Energy/
 * 6) /Vacuum Energy/

Stellar Formation & Evolution

 * 1) /Interstellar Medium/
 * 2) /Phases of Stellar Evolution/
 * 3) /Degenerate Stars/
 * 4) /Supernovae/
 * 5) /Compact Stellar & Relativistic Objects/
 * 6) /Close Binary Systems/

Stellar Structure

 * 1) /Hydrostatic Equilibrium/
 * 2) /Nuclear Reactions/
 * 3) /Energy Transport/

Star clusters and galaxies

 * 1) /Star Cluster/
 * 2) /Galaxies:Shapes and Evolution/

Quasars and Pulsars

 * 1) /Quasars/
 * 2) /Pulsars/

Appendices

 * A: Laws and Formulae
 * B: Astronomical Constants