The H-R diagram is a scatter graph of stars, a plot of stellar absolute magnitude or luminosity versus temperature or stellar classification. It is an important astronomical tool for understanding how stars evolve over time. Stellar evolution cannot... (View More) be studied by observing individual stars as most changes occur over millions and billions of years. Astrophysicists observe numerous stars at various stages in their evolutionary history to determine their changing properties and probable evolutionary tracks across the H-R diagram. In this activity, students plot both maxima and minima with corresponding stellar classifications for several variables, and then identify the type of variability: Cepheid, RR Lyrae, Mira or Semiregular. This activity includes background information, a teacher guide, a student activity, and accompanying worksheets. The American Association of Variable Star Observers (AAVSO) and The Chandra X-Ray mission have collaborated to develop this activity. (View Less)

In this activity, students will use a simulator of an orbiting X-ray observatory to observe a supernova remnant, the expanding gas from an exploded star. They will take X-ray spectral data, analyze them, and answer questions based on that data. This... (View More) resource consists of a manual and software for the Introductory Astronomy Lab Exercise, from CLEA (Contemporary Laboratory Experiments in Astronomy). The manual includes introductory activities for students, background information, an instructor's guide, a student handout, an answer key, a software user's guide, and a glossary. The student section of the activity starts on page 13. See Related & Supplemental Resources for a link to download the software. Note: the software is only available for Windows. (View Less)