last revised 3/9/18
NOTE: Many of these links require Java and/or Flash to operate properly. You will likely have to edit your security settings if you want to use them.

Galactic Structure 
Multiwavelength Milky Way website
Astronomical Coordinate Systems
Galactic Coordinates

Stars and Stellar Evolution 
UBVRI filters
SDSS filters
SDSS filters and redshifted spectra
Spectral classes
HR Diagram
Mass-Luminosity relation
Evolutionary track of the sun
Cluster HR diagram montage
Evolutionary tracks for different masses
Summary of stellar evolution

Physical Principles
Blackbody definition
Blackbody applet
Maxwell-Boltzmann distribution
Ideal Gas Law page
Kirchhoff’s Laws

Dust
Primer on Optical Depth U. Sussex page on radiative transfer and optical depth
Volk’s PN dust page
GOOD page on Interstellar Dust
Volk’s circumstellar dust page
M. Richmond’s Dust page

Atomic Physics
Paschen Series
Spectroscopic notation
Selection rules (van Dishoeck)
[O I] energy levels (van Dishoeck)
[O I] transitions (van Dishoeck)
[O III], [N II] levels (van Dishoeck)
[O II], [S II] levels (van Dishoeck)

Nebular Structure
GOOD nebular nebula summary by Westmoquette
Ionization Equilibrium notes from Robin Ciardullo at Penn State
Good Stromgren Sphere Notes from Robin Ciardullo at Penn State
Nebular Structure notes (Stasynska)
NEW: Optical/IR fly-through of the Orion Nebula
Volk’s page on PNe
Pogge’s page on “H II Regions”
tables and graphs from Osterbrock
Ionic Abundance calculator from STScI
Forbidden Line Temperature Calculator
Common emission lines in planetary nebulae
Many good applets by J. Koppen

Spectroscopy Links
Spectroscopy basics
Classic prism spectrograph
Fraunhofer diffraction
The Grating Equation
Blaze Angle
Overlapping orders 

Radio Astronomy, Infrared, and Millimeter Astronomy
Essential Radio Astronomy Course
The Infrared Universe
More on IR Astronomy
Microwave/Submillimeter Astronomy

CCD Links
CCD Tutorial at U. Oregon
CCD architecture and readout
QE and Thinning
Clocking and charge transfer
Java Simulation of CCD fabrication
Description of noise sources in a CCD

Probability and Statistics Links
Several good applets
Central Limit Theorem
Binomial applet
Poisson applet

Observing, Spherical Trig, Time & the Sky
EXCELLENT page for general observing concepts
Bob O’Connell’s observing course lectures
U. Nebraska’s GREAT applets:
Celestial Coordinates
Horizon Coordinates
Sidereal Time, Right Ascension and Hour Angle 

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