Spacecraft and Instrument
The entire spacecraft rotates to provide the necessary signal modulation. The four, fixed solar panels are designed to provide enough gyroscopic moment to stabilize rotation about the solar vector. This largely eliminates the need for attitude control.
The instrument detectors are nine high-purity germanium crystals. Each is cooled to cryogenic temperatures by a mechanical cryocooler. Germanium provides not only detections by the photoelectric effect, but inherent spectroscopy through the charge deposition of the incoming ray. The crystals are housed in a cryostat, and mounted with low-conductivity straps.
A tubular telescope structure forms the bulk of the spacecraft. Its purpose is to hold the collimators above the Ge crystals at known, fixed positions.
Read more about this topic: Reuven Ramaty High Energy Solar Spectroscopic Imager
Famous quotes containing the word instrument:
“In going where you have to go, and doing what you have to do, and seeing what you have to see, you dull and blunt the instrument you write with. But I would rather have it bent and dulled and know I had to put it on the grindstone again and hammer it into shape and put a whetstone to it, and know that I had something to write about, than to have it bright and shining and nothing to say, or smooth and well oiled in the closet, but unused.”
—Ernest Hemingway (1899–1961)