A Photometer for Obtaining SOI Data at the GEODSS ETS.
Abstract
A photometer has been installed in parallel with the GEODSS ETS B-telescope for the purpose of obtaining SOI data. The mounting technique used allows an object to be visually tracked simultaneously with the photometry. The photometer operates under computer control and takes 1000 samples per second in the photon counting mode of operation. A photomultiplier tube with a gallium arsenide photocathode was chosen in order to maximize the photon counting rate. Consideration of dark count indicates that the choice should be studied further. Measurements of stars show that reproducible and accurate (sigma approx. < 0.03') photometry can be obtained. High-speed data have been obtained for satellites as faint as 15th magnitude. These records show a great deal of detail and promise to provide a wealth of data for SOI. The overall performance of the system is highly satisfactory and should provide a useful benchmark in the specification and design of future systems. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 03, 1978
- Accession Number
- ADB032502
Entities
People
- John M. Sorvari
Organizations
- Massachusetts Institute of Technology