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The ClassAction Browser V2 is currently not functional (although the Native App version works quite well). It will be uploaded as soon as it is functional. Individual modules focusing on a specific topic are available below. A complete list of ClassAction questions is also available.

ClassAction modules consist of questions and resources designed to encourage student engagement in the classroom. More details can be found on the overview, how to use and pedagogy pages.

The modules below roughly follow the outline of most introductory astronomy textbooks. Clicking on a module name opens the module in a pop-up window.

Module Name Topics Included Number of Question Files
Introductory Concepts This module covers the standard first chapter in most textbooks usually entitled something like "Scale of the Cosmos" which includes organizational bins Solar System, Galaxy, and Universe, scientific notation, metric prefixes, special units, speed of light, and look-back time. Introductory questions on statistics, pressure, temperature, and graphing are planned. 17
Basic Motions & Ancient Astronomy This module surveys basic observations in the sky, angular diameter, celestial timekeeping, constellations,the importance of astronomy to ancient peoples, and the Greek Astronomers (Aristarchus & Eratosthenes). 15
Coordinates & Motions Coordinate systems (terrestrial, celestial equatorial, and horizon), celestial sphere, ecliptic, seasons, hours of daylight, meridional altitude, paths of the sun, and declinations ranges. 49
Lunar Cycles Phases, eclipses, synchronous rotation, and tides. Special emphasis is placed on the geometrical cause of phases. 27
Renaissance Astronomy The works of Copernicus, Kepler, Galileo, & Newton including sidereal/synodic periods, eccentricity, elongation, and special planetary configurations. Special emphasis is placed on Kepler's Laws. 40
Light & Spectra Types of spectra, EM spectrum, electron energy levels, Wien's Law, Stefan-Boltzmann Law, the Doppler shift, and inverse square law. 44
Telescopes and Astronomical Instruments Refraction, reflection, telescopes of different types and focal arrangements, powers of a telescope (light gathering power, resolving power, magnification), CCDs, spectrographs 15
Sun and Solar Energy Nuclear energy, thermal transport, hydrostatic equilibrium, solar activity (Sunspots), differential rotation, charged particles in magnetic fields 21
ISM & Star Formation Nebulae, ISM, preferential scattering, giant molecular clouds, star formation 10
Stellar Properties I Stellar magnitudes, luminosity, stellar velocities including the doppler shift and proper motion. 21
Stellar Properties II HR Diagram, luminosity function, distance determination including parallax and spectroscopic parallax, stellar radii, stellar masses. 24
Binary and Variable Stars Types of binaries (visual, astrometric, spectroscopic, spectrum, & eclipsing), light curves, and radial velocity curves. This module will also look at concepts related to observing variable stars. 30
Stellar Evolution HR Diagram evolutionary tracks, core stages, stages of the sun's evolution, planetary nebulae, supernovae, end states of stars. Special emphasis has been placed on coordinating locations on HR Diagram evolutionary tracks with energy production in the core of the star. 32
Milky Way Galaxy Characteristics of disk and halo stars, rotation curves, spiral arms, importance of variable stars. 17
Galaxies Types of galaxies and their characteristics, the Hubble Tuning Fork Diagram, galactic evolution, active galaxies, quasars. 18
Cosmology Hubble's Law, characteristics of the expansion, the Big Bang. 17
Solar System Characteristics Orbits of the planes, characteristics of terrestrial and jovian planets, cratering rate, nuclear half-life. 22
ExtraSolar Planets Strong emphasis on the radial velocity and transit techniques. 28
Terrestrial Planets Crater maps, periods of rotation and revolution of the planets, evolution and retention of planetary atmospheres. 15
Jovian Planets Jovian Planets and their moons. 22
Solar System Debris Meteors, meteorites, asteroids, comets, and the Kuiper Belt. 27

Specialty Modules

Module Name Topics Included Number of Question Files
Light and Spectra Concept Inventory This module specifically targets concepts covered on the Light and Spectra Concept Inventory. It is very similar to the Light & Spectra module but does not include questions on flux and inverse square and does include some questions involving the luminosity of stars and its dependence on temperature and radius. 38