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3 Dimensional Plots of Counts vs Energy Displayed as Functions of Time (Digitized)


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

Time span: 1969-11-19 to 1974-01-25


This data set consists of digital TIFF images of machine-drawn plots of data from the Total Ion Detector (TID) part of the Apollo 12 ALSEP/SIDE. The data displayed are 20-minute average spectra of the detector counting rates versus energy channel for all 20 channels from 10 eV through 3500 eV. A background count is also plotted at each end of each spectrum as a reference level. The instrument had a "calibration mode" of 8 steps after each 120 steps (6 spectra) in normal mode. These housekeeping items are not included in this data set, but can be found in the full-resolution data set PSFP-00163.

Successive spectra are plotted at the appropriate intervals on an oblique time axis, resulting in a 3-dimensional plot effect. Each plot consists of 4 panels, covering local midnight to sunrise, sunrise to noon, noon to sunset, and sunset to midnight. Start and stop times of the data in each panel are printed, and a large label on the plot identifies the Apollo mission number, year, and start day and time of the plot (not necessarily the start of the data). Each plot image is in a file by itself, and the file name identifies the instrument and the start day and year of the plot. Various charged particle regimes of the magnetosphere are visibly apparent in these plots. The plots also provide a convenient way to assess the ion population during each lunation and to identify various types of events for follow-up with the full resolution digital data or for comparison with data from other instruments. Similar data sets are available for the SIDE instruments on Apollo 14 and 15, in data sets PSFP-00717 and PSFP-00718, respectively, for the lunation plots. The start times and the stop times of the full-resolution data sets can be different from those of the lunation plot data sets. In addition, there are numerous data gaps of a few hours to a few days, usually in midday.

These images are high-resolution scans of a photos made by NSSDCA of the data provider's large-format paper plots.


  • Space Physics: Magnetospheric Studies
  • Planetary Science: Fields and Particles

Additional Information



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



NameRoleOriginal AffiliationE-mail
Dr. H. Kent HillsData ProviderADNET Systems, Inc.
Dr. H. Kent HillsGeneral ContactADNET Systems, Inc.
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