Exploring the Unknown - NASA's History Office

EXPLORING THE UNKNOWN 239
terometer radars, passive microwave radiometers, and UV line scanners in 1965 and plan
to add more advanced multispectral cameras, metric and panoramic cameras, more
advanced infrared scanners, infrared spectrometers and passive microwave imagers in
1966. The studies and the aircraft program are planned to be carried out on a continuing
basis to provide for economical testing of instrumentation over sites of known characteristics
prior to orbital testing.
As a result of these activities the user community has identified and specified candidate
instruments for orbital test. The initial and most urgent of these are a wide range
spectral scanner (0.3–13 microns) covering the near UV, visible and part of the IR spectrum
(190 meter resolution) and a multispectral synoptic photographic system (of
approximately 30 meters resolution). NASA is currently planning incorporation of these
instruments into an already planned flight in 1969.
A rather completely instrumented natural resources satellite is being considered for
flight in 1970 or 1971 involving the following instruments:
Metric Cameras
Panoramic Cameras
Multispectral Tracking Telescope
Multispectral Synoptic Cameras
Imaging Radars (8.0 gc)
Radar Altimeter/Scatterometers (0.4 and 0.8 gc)
Wide Range Spectral Scanner (0.3–13 microns)
Infrared Long Wavelength Spectrometer (18–16 microns)
Infrared Short Wavelength Spectrometer (0.4–2.5 microns)
Infrared Radiometer (10–12 microns)
Passive Microwave Imager (9.0 gc)
Passive Multichannel Microwave Radiometers (0.4–21 cm)
UV Imaging Spectrometer (3900–4900 Angstroms and 5800–6800 Angstroms)
Laser Altimeter/Scatterometer
Absorption Spectrometer (UV, visible, IR)
Chirp Radar System (75–450 mc’s)
Gravity Gradiometer
Magnetometer System (triaxial fluxgate and rubidium vapor)
Flight test of this entire group of instruments simultaneously is highly desirable
because the cross correlation of data from various portions of the electromagnetic spectrum
acquired under similar lighting and weather conditions will yield far more information
than data acquired at separate times by individual instruments.
If successful and needed, a repeat of this satellite is being considered for flight in
1971–72 to continue the development of the technology and the ability to handle and
analyse [sic] accumulated data.
[3] Orbital Requirements
During the experimental phase of this program (pre-1975) the natural resource users
require data to be collected periodically over a number of natural and cultural resources
test sites. These sites must be readily accessible and available for study by well trained scientists.
Many of the sites essential to this program fall within the United States both
because of the subject matter involved (such as land use in metropolitan areas, water pollution
in Great Lakes, water resources in northeast and arid west, geothermal power sites
in Pacific Northwest etc.) and because of the ready availability of trained personnel for
ground control studies. Orbital inclinations of at least 480 are therefore extremely important
during the experimental phases of this program. It should be emphasized however,