NASA
Nasa: Imagine the Universe: X Ray Binary Stars
Site provides a brief introduction to binary stars. Additional resources for students and teachers on this topic are offered as well as related topics.
NASA
Nasa: Imagine the Universe: Neutron Stars and Pulsars
Discover what neutron stars and pulsars are and view pictures of them. Includes links to additional resources and lesson plans.
NASA
Nasa: Imagine the Universe: "Twinkle, Twinkle (Really Fast!), Little Star"
"The Rossi X-ray Timing Explorer has discovered neutron stars that emit streams of X-rays pulsing over 1,000 times a second." Visit this site to read the rest of this article. Site offers additional resources as well as a Teacher's Corner.
NASA
Nasa: Imagine the Universe: Supernovae (Advanced)
Supernovae are divided into two basic physical types, including a description of supernova types and how they are classified based on the existence of hydrogen spectral lines. Definitions of key terms are provided.