This website is kept for archival purposes only and is no longer updated.
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Instrument
The NIGHTGLOW instrument consists of three telescopes (large image) (each has a 14" diameter mirror and a 19" focal length - an f/1.4 design) instrumented with two photomultiplier tubes (PMTS) (large image). A PMT is a very sensitive device for converting light into an electronic signal. A filter is used to limit the light entering the telescopes to wavelengths between 300 - 400 nm - in the (invisible) near ultra-violet part of the spectrum. The electronics (large image) are controlled by a small format 386 microprocessor.
One of the three main telescopes looks down at all times, while the other two rotate. The motor and mechanism that do the rotation are shown in this large image. The two telescopes that rotate view the ground, the horizon and the UV glow at high altitudes (above the balloon at ~90 km). This high altitude nightglow comes from the excited states of the gases in the atmosphere, mainly nitrogen and oxygen.
This file was last modified January 31, 2003 |
