Facilities > GBT > Other Telescopes > 40 Foot Telescope

40 Foot Telescope

by Karen ONeil last modified Apr 08, 2014 by Dong-Chan Kim

40 Foot Telescope

The Forty-foot Telescope, was constructed in the early 60s for the purpose of determining if radio sources are variable. As far as we know, it was the first completely automated telescope. After sitting idle for nearly 2 decades, the 40' was recommissioned in 1987 as an educational telescope. Students ranging from 5th graders to graduate students use the telescope to investigate the radio universe. RARE CATS teachers complete extensive research projects using the 40', and Chautauqua Short Couse participants have access as well. In addition, amateur astronomers routinely make use of this telescope.

The Forty-foot Observer's Manual is available as a PDF file. You will need Adobe Acrobat Reader to view this file.

Forty-foot data , in ascii format, is available. You will see four columns of numbers: Right ascension (celestial longitude), declination (celestial latitude), data points for each of our two receiver channels: Channel A and B. Forty-foot calibration numbers are given for the time when the data was collected. These may not be current values. The best way to view this data is to import it into a spreadsheet and create a graph. Microsoft Excel works well. Graphed, the data will then resemble a stripchart recording. Those of you who have used the Forty-foot, will immediately know what to do at that point!