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Apollo Lunar Sounder Experiment on 70-mm Film (Digitized)


Availability: Data Identified but not Received

Time span: 1972-12-11 to 1972-12-16


This collection consists of digital scans of 70-mm filmed plots of HF-1 data at a frequency of 5 MHz processed using the Environmental Research Institute of Michigan Precision Optical Processor Facility. The HF-1 system was designed to provide deep exploration with some loss of resolution compared to the HF-2 system. Chirped pulses were transmitted at a rate of 400 pulses per sec. The HF-1 image was processed with an azimuth demagnification of 69.85. The frequency-plane aperture was set so that slant range and azimuth resolution were 300 m. Range weighting was used to reduce range side lobes, degrading range resolution by a factor of approximately 2.2 times. The film scale parameters are 7.16 x 10 to the minus 2 mm per sec along the film and 4.04 x 10 to the 4 mm across the film. Locations can be determined by measuring from the breaks in the data when the sounder was turned on and off. See table 1 in collection PSPG-00079, Apollo Lunar Sounder Supporting Data on Microfiche. Also see PSPG-00079 for explanatory information about the HF-1 optically processed lunar sounder data. A holographic viewer is required to interpret the data on these plots. Due to instrument variations, different viewers could give results which don't agree with each other.

For this digitization effort the NSSDCA scanned the source 70-mm film collection PSPG-00213 at a resolution of 400 dots per inch and output each frame on the film as one TIFF file. The NSSDCA also combined groups of these TIFF images into multipage PDF files to facilitate browsing. Both formats are included in this collection.


  • Planetary Science: Geology and Geophysics

Additional Information



Questions and comments about this data collection can be directed to: Ms. Stephanie A. McLaughlin



NameRoleOriginal AffiliationE-mail
Mr. G. F. AdamsGeneral ContactUniversity of Michigan
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