The southern H-alpha survey: An amateur-professional collaboration

We are conducting a wide-angle imaging survey of the southern sky at 656.3 nm wavelength, the H-alpha emission line of hydrogen. Each image of the survey covers an area of the sky 13 degrees square at an angular resolution of approximately one arcminute, and reaches a sensitivity level of one Rayleigh (6 x 10(-18) erg x cm(-2) s(-1) arcsec-2), corresponding to an emission measure of 2cm(-6) pc, and to a brightness temperature for microwave free-free emission of 6 microKelvins at 30 GHz. The survey is being done with a CCD detector, a commercial camera lens, and narrowband interference filters, mounted on a robotic telescope platform located at Cerro Tololo Inter-American Observatory in Chile. As of July 1999 the data-gathering phase of the survey was 99% complete. This project is an example of how amateurs and professionals can combine their technical, scientific, and organizational talents to produce high quality science.