Study structured tutorials for aspiring astronomers in cosmology, planetary movement, galaxy properties and stellar evolution.

Dive into CCD images of galaxies, nebulae and star clusters. Includes both monochrome and WCMY color images.

Encyclopedia entry describes a collection of hundreds of millions of stars orbiting around a common center of gravity.

Encyclopedia article describes these small, irregular galaxies, which are near the Milky Way and the constellations Dorado and Tucanan.

Article describes the January 2001 discovery of a galaxy supercluster. Learn why its existence violates theories of the history of the universe.

Astrophysicists are using supercomputers to simulate a collision between the Andromeda galaxy and the Milky Way. Watch a QuickTime video of the simulation.

Students for the Exploration and Development of Space provides this brief overview of spiral, lenticular, elliptical and irregular galaxies.

Learn about the functioning of stars, their life cycle, and how they generate energy.

Detailed review of this type of galaxy includes equilibrium models, observation notes and speculation about formation processes.

Presents an illustrated guide to the cosmos, the big bang theory, and cosmic background radiation.