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Apollo 12 ALSEP ARCSAV Suprathermal Ion Detector/Cold Cathode Ion Gage Level 1b Raw Cleaned (Corrected) Binary Files

NSSDCA ID: PSFP-00742

Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)

Time span: 1975-04-03 to 1975-07-01

Description

The astronauts on the Apollo missions deployed a set of scientific instruments that were collectively known as the Apollo Lunar Surface Experiments Package (ALSEP) at each of the Apollo 12, 14, 15, 16, and 17 landing sites. The ALSEP instruments operated from the time of deployment to September 1977 at each site. This collection from the Apollo 12 site consists of cleaned (corrected) binary files of Suprathermal Ion Detector Experiment (SIDE) and Cold Cathode Ion Gage Experiment (CCIG, also known as CCGE) data extracted from NASA's original ALSEP data archival tapes (also known as ARCSAV tapes) that recorded rearranged and time-edited, raw (unprocessed) data transmitted from the Moon. This collection covers the period of April 3, 1975 through July 1, 1975.

An ASCII version of these data is available on-line at the Planetary Data System: https://pds-geosciences.wustl.edu/lunar/urn-nasa-pds-a12side_ccig_raw_arcsav/.

Details

From April 1973 to February 1976, approximately 5000 ARCSAV tapes were generated at the NASA Johnson Space Center. They were 7-track, digital, open-reel magnetic tapes. One ARCSAV tape contained a 24-hour continuous recording of the data for all the instruments deployed at one of the Apollo landing sites. In the years following the conclusion of the Apollo program, all of these tapes were lost. In the year 2010, 439 of these tapes, containing data from April 2, 1975 through July 1, 1975, were recovered at the Washington National Records Center [1].

A Level-0 data set (NSSDCA collection PSPG-00912) was generated, which consists of binary files of intermeshed experiment data 'as read' and extracted from those 439 ARCSAV tapes, but without corrections for obvious bit errors. These obvious bit errors were then corrected to make the Level-0a data set NSSDCA PSPG-00917.

The present Level-1b data set consists of 90 daily binary files of intermeshed SIDE and CCGE data extracted from the Level-0a files (PSPG-00917). Each binary file consists of SIDE- and CCIG-related ALSEP data words, containing science measurements and housekeeping and command verification information.

In order to extract data of interest, the user should consult: [2] which describes the format of the files and lists the SIDE- and CCIG-related ALSEP data words captured in these files; and [3] which describes in detail the bit-level content of ALSEP data words. (Some words contain packed, bit-level data.)

For detailed information on the individual ALSEP experiments, see [4]. For the operational history of the individual experiments, see [5]. Users interested in the Level-0 and Level-0a data sets, which are noted above, see [6] for descriptions of those binary files.

The computer programs and supplemental inputs used to produce the binary data in this collection are available in this selected reference by Nakamura (2020): https://nssdc.gsfc.nasa.gov/misc/documents/b56523.pdf

References:

[1] Nagihara, S., et al., Search and Recovery Efforts for the ALSEP Data Tapes, 42nd Lunar and Planetary Science Conference, held March 7-11, 2011 at The Woodlands, Texas, Lunar and Planetary Institute Contribution No. 1608, p. 1103, Mar. 2011. (https://www.lpi.usra.edu/meetings/lpsc2011/pdf/1103.pdf )

[2] Nakamura, Y., Description of Apollo ALSEP ARCSAV Level-1b Raw Binary File Formats by Experiment, Institute for Geophysics, University of Texas, Nov. 2017, updated Mar. 2018. (NSSDCA document B56517-000A, https://nssdc.gsfc.nasa.gov/misc/documents/b56517.pdf )

[3] Apollo Lunar Surface Experiments Package Archive Tape Description Document, JSC-09652, NASA Johnson Space Center, Houston, Texas, USA, May 1975. (https://repository.hou.usra.edu/handle/20.500.11753/42 ; also available as NSSDCA document B56514-000A, https://nssdc.gsfc.nasa.gov/misc/documents/b56514.pdf )

[4] Lauderdale, W. W., and W. F. Eichelman, Apollo Scientific Experiments Data Handbook, NASA Technical Memorandum, NASA-TM-X-58131, JSC-09166, Houston, Tex., Aug. 1974, updated Aug. 1976. (https://repository.hou.usra.edu/handle/20.500.11753/17 or https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19760007062.pdf ; also available as NSSDCA document B22807-000A, https://nssdc.gsfc.nasa.gov/misc/documents/b22807.pdf )

[5] Bates, J. R., et al., ALSEP Termination Report, NASA Reference Publication, NASA-RP-1036, Houston, Tex., Apr. 1979. (https://repository.hou.usra.edu/handle/20.500.11753/16 or https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790014808.pdf ; also available as NSSDCA document B32116-000A, https://nssdc.gsfc.nasa.gov/misc/documents/b32116.pdf )

[6] Nakamura, Y., Description of Apollo ARCSAV tape files as produced by JBI, DBDS and KDM, with Addendum, Institute for Geophysics, University of Texas, Austin, Texas, 29 Nov. 2016, updated Dec. 2016 and Oct. 2017. (NSSDCA document B56515-000A, https://nssdc.gsfc.nasa.gov/misc/documents/b56515.pdf )

Disciplines

  • Planetary Science: Atmospheres
  • Planetary Science: Fields and Particles
  • Planetary Science: Geology and Geophysics

Additional Information

Spacecraft

Experiments

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

 

Personnel

NameRoleOriginal AffiliationE-mail
Dr. Yosio NakamuraGeneral ContactUniversity of Texas, Austinyosio@utig.ig.utexas.edu

Selected References

  • Lauderdale, W. W., and W. F. Eichelman, Apollo scientific experiments data handbook, NASA, TM-X-58131, Houston, Tex., Aug. 1974, updated Aug. 1976.
  • Bates, J. R., et al., ALSEP termination report, NASA, RP-1036, Wash., DC, Apr. 1979.
  • Nakamura, Y., Apollo Lunar Surface Experiment Package Archive Tape Description Document (ARCSAV), NASA Johnson Space Center, JSC-09652, Houston, TX, May 1975.
  • Nakamura, Y., Description of Apollo ARCSAV tape files as produced by JBI, DBDS and KDM, with Addendum, Institute for Geophysics, University of Texas, Austin, Texas, 29 Nov. 2016, updated Dec. 2016 and Oct. 2017.
  • Nakamura, Y., Description of Apollo ALSEP ARCSAV Level-1b Raw Binary File Formats by Experiment, Institute for Geophysics, University of Texas, Austin, Texas, Nov. 2017, updated Mar. 2018.
  • Nakamura, Y., Apollo ARCSAV Level 1b (Raw Cleaned Binary) File Processing Programs and Supplementary Input Files, Institute for Geophysics, University of Texas, Austin, Texas, Apr. 2020.
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