Measurement of the radiation from thermal and nonthermal radio sources

The widespread use of the internet has enabled complex instrumentation to be available remotely and made it possible for students to use facilities to which they might otherwise not have access. Internet access to radio astronomical observatories, including the 37 m radio telescope at the Massachusetts Institute of Technology Haystack Observatory, has opened up new possibilities for undergraduate laboratory activities and research. This capability allows undergraduates to acquire and analyze radio astronomical data and investigate astrophysical systems that cannot be investigated using optical telescopes. We describe a radio astronomical activity using the spectral index to investigate the difference between thermal and nonthermal radiation and the sources that emit these forms of radiation. © 2005 American Association of Physics Teachers. @DOI: 10.1119/1.1858485#