This temperature controlled insulated container, or "Cold Box" was used to house photoelectric photomultipliers used with telescopes at the Kitt Peak National Observatory (KPNO). The photoelectric photometer is a device for measuring the amount of light gathered by a telescope from point-like sources such as a star or the nucleus of a galaxy. Light collected by a telescope that had then been processed through a diaphragm and filters in the photometer head (Catalogue #A20000791000) was routed onto the face of a photoelectric photomultiplier tube inside the red container. This tube converted the light to an electrical signal and amplified that by a cascade effect. In operation, the box was filled with dry ice to maintain the tube at the low temperature required for enhanced sensitivity and low thermal noise. This box was built at KPNO in 1974 and used extensively for measuring light from astronomical objects; it was donated by the Observatory to NASM in 2000.

Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Object Details

Country of Origin

United States of America

Type

INSTRUMENTS-Scientific

Manufacturer

Kitt Peak National Observatory

Dimensions

3-D: 33 x 40.6 x 38.1cm (13 x 16 x 15 in.)

Materials

Metals
Glass vacuum tube
Electronics
Foam insulation

Inventory Number

A20000791001

Credit Line

Gift of Kitt Peak National Observatory

Data Source

National Air and Space Museum

Restrictions & Rights

Usage conditions apply
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