As I discussed in my blog post on December 8, 2009, visible light is only one portion of the electromagnetic spectrum used for astronomical observations. Astronomers routinely observe the radiation emitted by objects at other wavelengths – like infrared. Radio astronomers have been studying the radio waves emitted by astronomical objects since the 1930's. Radio astronomy is an area that I plan to write about frequently in the future. While radio astronomy isn’t as common among amateur astronomers as visible light observing it is still an exciting area that should be considered by amateurs looking for new observing opportunities.

One of the best internet resources I have found for learning about radio astronomy is ASTRON – the Netherlands Institute for Radio Astronomy. ASTRON was founded in 1949 and currently operates two state-of-the-art observing facilities: the Westerbork Synthesis Radio Observatory (WSRT) and LOFAR (the Low Frequency Array).

The ASTRON web site is very well done and quite interesting. In particular I would recommend checking out the Publications page (pay particular attention to the Newsletters section).

Newsletters are published two times per year and the content is excellent. For example, the most recent issue (December 2009) has articles covering topics like:

• The current status of LOFAR (the Low Frequency Array)
• Millisecond pulsars and the discovery of a "missing link" in the process that creates them
• Gravitational lensing
• Seven high school students known as the "spacegirls" who won a Dutch space competition called CanSat
• Student projects done as part of the Summer Student Programme 2009. (By the way, the deadline for applications of the Summer Student Program 2010 is February 1, 2010.)
• Water in the early universe
• And a LOT more – the newsletter is 44 pages long

If you are at all curious about radio astronomy or radio astronomers be sure to check out this excellent site.