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Introduction
This proposed Lunar Data Project will identify and reformat lunar data uniquely held by the NSSDC and archive and make the data accessible online to the lunar exploration community. The National Space Science Data Center (NSSDC) maintains over 500 NASA data sets from astronaut and robotic missions to the Moon. It is the most comprehensive archive of 20th century lunar data in the world. Most of these data sets are unique and are not in the Planetary Data System (PDS) since they are primarily image- and microfilm-based dating from the Apollo era. These data sets are archived and well maintained, and are held in the offline portion of the permanent NSSDC archive. High-level information about these data is accessible online and requests for duplication of many of these data have occurred steadily over the last 30 years. Utilization of the data in the current nonelectronic format is cumbersome. The expertise and most of the equipment needed to achieve this task already exists at the NSSDC. Figure 1 summarizes the project and how the results will be utilized by the exploration community. As indicated by the attached letter (Appendix 6), this effort is supported by John Young, Commander of the Apollo 16 mission, who collected a portion of the data himself. Making use of this data before the scheduled lunar missions take place will in effect allow us to get to the Moon ahead of the hardware.
1.1 Relevance to NASA
The President has challenged NASA to “extend human presence across the Solar System, starting with a human return to the Moon before the year 2020, in preparation for human exploration of Mars and other destinations.” In response, Administrator O’Keefe has established a set of goals for space exploration beyond low-Earth orbit, see Figure 2. These goals emphasize exploration, though science is also a part of the lunar missions. Consistent with the NASA Vision and Mission, NASA exploration programs will seek profound answers to questions of our origins, whether life exists beyond Earth, and how we could live on other worlds. In order to support exploration of the Moon, key data will be needed to determine landing sites based on local resources, terrain, environment, and other lunar characteristics for which much data already exists. The current NASA vision is a continuation of the early lunar flights of the 1960s. Most instruments flown or left on the Moon had a specific purpose with the ultimate goal of enabling future exploration. The Saturn V rockets at both Kennedy and Johnson Space Centers are a monument to the midstream cancellation of the program. It is important to take advantage of the enormous amount of information produced by these previous lunar missions. We cannot afford to recreate existing lunar data sets. The first new mission to the Moon, scheduled for launch in 2008, will be limited and should therefore concentrate on obtaining data that are needed, taking advantage of and supplementing the data that already exists in the PDS and the NSSDC. Later robotic missions to the lunar surface will require an understanding of the environment which only the in-situ Apollo experiments can give. This effort will build on and extend previous NASA accomplishments at a low cost. Providing rapid access to currently offline key lunar data sets in the NSSDC in a Lunar Exploration Enabling Database (LEED) will support the President’s Moon/Mars initiative and should be important in determining the requirements of the upcoming new lunar missions.
Figure 2 – The Lunar Data Project will enable the successful implementation of the exploration initiative to meet the goals of the lunar exploration vision.
1.2 Lunar Data Key Questions and Goals
There are two primary reasons that knowledge of the lunar environment is essential to enable extended robotic and human exploration. The first is that all hazards and deleterious environmental effects must be recognized and understood to enhance astronaut safety, including risks posed to equipment as well as to astronauts. Potential hazards include the charged and energetic particle environment, the cosmic ray and radiation environment, the ambient atmosphere, lunar dust, and landing obstacles such as boulders, craters, and sharp rocks. The second reason is to locate potential resources on the Moon, particularly water ice, but also optimal locations for solar energy and safe landing and building sites. Much of the data returned from the Moon during the Apollo program and archived at the NSSDC is ideally suited to help meet the goal of understanding the lunar environment to mitigate hazards and make full use of whatever resources might be available (Figure 3). A gap analysis of the current data would also help determine lunar data which should be collected in the future. As evidenced by the fact that most Apollo Lunar Surface Experiment Package (ALSEP) data are not referenced or mentioned in such compendiums as the Lunar Sourcebook (Cambridge, 1991) it is clear that the information is not widely known to the community.
Figure 3 - The near side of the Moon has been extensively explored by the Soviet Luna (red) and U.S. Surveyor (yellow) and Apollo (green) missions.
1.3 Lunar Data Evaluation
A lunar data evaluation team consisting of a group of Goddard lunar and data experts (see Section 2.1) was formed in February 2004 to review the extensive uniquely held lunar data at the NSSDC. The panel provided an independent initial ranking of these unique lunar data sets as to their potential importance in supporting the President’s initiative. The prioritized list is one of the bases of this proposal. (see Section 2.3)
The purpose of the Lunar Data Project is to identify lunar data uniquely held by the NSSDC that is of vital importance in supporting the President’s Moon/Mars initiative, reformat digital data, digitize analog data at the appropriate resolution and place that data online (web accessible) with associated metadata for access by the entire exploration community. A secondary goal is to determine if data exists from other U.S. sources and the Soviet lunar exploration program to enhance or improve the archive, and if so, prepare to utilize it as well.
The potential impact of the Lunar Data Project is to improve safety for both machine and people, limit duplication of efforts, reduce costs, aid in the development of mission architectures and enhance spacecraft and instrument design.
2.0 Lunar Data
2.1 Lunar Data Evaluation Team
The lunar data evaluation team consisted of Paul Lowman (Chairman), Gregory Leptoukh, Patrick Taylor, Dave Rubincam, and Will Webster (Figure 4). In the meeting of the team and NSSDC personnel on 27 February 2004, lunar data sets were reviewed with particular attention to their relevance to lunar hazards, resources, and the long-term effects of the lunar environment on equipment.
Figure 4 – The Lunar Data Evaluation Team (L to R) Gregory Leptoukh, Dave Rubincam, Paul Lowman, Will Webster (not pictured: Patrick Taylor) reviewed the data held at the NSSDC for relevance to future lunar exploration.
A number of important points were brought up at the meeting:
• The Apollo landings were from the beginning assumed to lead to the establishment of a lunar base and detailed concepts were developed beginning in 1962. For this reason, many of the Apollo surface experiments were intended to characterize the lunar surface environment for purposes of a long-term exploration program. Such a program did not materialize, but the data collected are still valuable for this purpose.
• Much of this lunar data has not been thoroughly examined, in part because of the large amount of data returned over time by some of these experiments, in part because of the difficulty of accessing data stored on microfilm or microfiche, and in part because of the termination of funding for the Apollo program.
• A thorough examination of more user-friendly digital versions of this data with current high-speed computers and sophisticated software could prove fruitful in characterizing the lunar environment.
• Historical, long-term data are the only way to observe changes in the lunar environment over periods of time characteristic of proposed extended human missions.
The report of the Lunar Data Evaluation team is included in Appendix 7.
2.2 The Data
The ALSEPs (see Table 1) placed on the Moon by Apollo 12, 14, 15, 16, and 17 are the only long-term experiments ever run on the surface of the Moon. The ALSEPs returned data to Earth from their deployment in 1969-72 until they were switched off in 1977. Currently the Lunar Laser Retroreflectors are the only part of the ALSEPs still in use, providing a valuable indication of the long term effects of the lunar surface environment on hardware. The ALSEP data represent a unique and irreplaceable window into the Moon's surface environment. Data from the following ALSEP experiments were judged by the team to be of highest priority for restoration and digitization for future lunar exploration: the Solar Wind Spectrometer (Apollo 12 and 15), the Suprathermal Ion Detector (Apollo 12, 14, and 15), the Charged Particle Lunar Environment Experiment (Apollo 14), and the Cold Cathode Ion Gauge (Apollo 14 and 15). These data were all deemed critical to understanding the effect of the lunar environment on equipment and astronauts. The ALSEP work tapes are also important in that they contain housekeeping and engineering as well as all science data from the ALSEP central station and the individual experiments which would be useful in determining the long-term effects of the lunar environment on equipment.
It was also determined that the soil mechanics data from Apollo 15 and 16 and dust detector data from the Apollo 14 and 15 ALSEPs would be important for designing robotic and astronaut vehicles and for planning construction on the Moon. Photographic data sets were also considered, in terms of their uses both in avoiding landing hazards and locating resources and viable areas to establish lunar habitats. The Apollo Panoramic Photography was judged to be the most useful of the data for digitization at high resolution. This data will be digitized at high but not full resolution initially to provide mission planners with data from which they can choose areas of interest and then full resolution scans or the actual hard copy photographs can be made available.
Other experiments which were deemed lower priority, but still considered to have the possibility of providing important data for future exploration, were the Apollo 15 and 16 Subsatellite Lunar Particle Shadows and Boundary Layer experiment and the Alpha Particle Spectrometer data taken from orbit on Apollo 16 to characterize the lunar environment, the Far Ultraviolet Spectrometer from orbit on Apollo 17 to evaluate the Moon as a platform for studying Earth, and the ALSEP Passive Seismometers on Apollos 12, 14, 15, and 16, to judge the potential for disturbances to sensitive instruments.
Table 1 – Apollo Lunar Surface Experiment Package Locations. The Apollo landing sites represent a diverse sample of lunar terrains. See Figure 3 for a map of the near side of the Moon showing landing site locations.
ALSEP
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Location
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degrees N latitude
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degrees E longitude
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Apollo 12
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Ocean of Storms
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-3.01084
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-23.42456
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Apollo 14
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Fra Mauro
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-3.64450
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-17.47753
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Apollo 15
|
Hadley Rille
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26.13407
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3.62981
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Apollo 16
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Descartes
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-8.97577
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15.49649
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Apollo 17
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Taurus-Littrow
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20.18935
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30.76796
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2.3 Detailed Discussion of Data and Experiments
The Suprathermal Ion Detector Experiment (SIDE) was part of the Apollo 12, 14, and 15 ALSEPs. It measured positive ions reaching the lunar surface, including magnetospheric ions and those generated from ultraviolet ionization of the lunar atmosphere and from the free-streaming solar wind/lunar surface interaction. Flux, number density, velocity, and energy/unit charge were determined. A mass spectrum of the ion flux from 0.2 to 48.6 eV and an energy spectrum from 10 to 3500 eV were determined for each 24 second interval. Data are archived in the form of magnetic tapes written in Science Data Systems (SDS) format and plots and data listings on microfilm. A set of Principal Investigator (PI) tapes with raw data covering later periods also exists. All pertinent data should be available from the magnetic tapes and available hardcopy documentation. We also have hardcopy plots, which may be scanned for inclusion with the data set.
The Charged Particle Lunar Environment Experiment (Apollo 14) consisted of electrostatic analyzers, which measured the energy spectra of low-energy charged particles striking the lunar surface. The experiment yielded 1.2-s accumulated counts of electrons in 18 energy windows between 40 eV and 20 keV, and counts of ions in 12 energy windows between 0.17 keV and 20 keV. The data are in the form of magnetic tapes in SDS binary format and microfilm plots; all necessary data are contained on the tapes and available hardcopy documentation.
The Solar Wind Spectrometer was part of the ALSEP packages on Apollos 12 and 15. The experiment consisted of a set of modulated Faraday cups opened toward different, but slightly overlapping, portions of the lunar sky. The instrument was used to observe the directional intensities of the electron (6-1330 eV) and positive ion (18-9780 eV) components of the solar wind and magnetotail plasma that strike the surface of the Moon. The data are in the form of magnetic tapes written in Binary Coded Decimal (BCD) format on a UNIVAC 1108 and microfilm plots.
The Cold Cathode Ion Gauge, included in the ALSEPs on Apollos 14 and 15, was designed to measure the amount of gas present on the lunar surface with a detection capability from 2.E+5 to 1.E+11 particles/cubic cm, measured in a 2.5 minute cycle. The gauge head was in contact with the lunar surface. Data consist only of plots of the atmospheric density and temperature as functions of time on microfilm. The temperature data from the gauge are also available in the SIDE data.
The Apollo 15 and 16 Lunar Particle Shadows and Boundary Layer Experiment used particle telescopes and electrostatic analyzers on a subsatellite orbiting the Moon to study the plasma regimes through which the Moon moves and the interaction of the Moon and plasmas. The experiment measured electron energies from 0.53 to 520 keV and protons from 20 to 700 keV. The data are available on magnetic tape as 10 minute and 2 hour averages. Plots of higher resolution (24 second) averages are held on microfilm.
The Soil Mechanics Experiment carried on Apollos 15 and 16 consisted of a self-recording penetrometer with interchangeable load plate and three cones of various diameters. The data from the experiment is contained on microfilm in the form of tables and plots showing the depth of penetration at each site as a function of stress on the penetrometer.
The Dust Detector Experiment (Apollo 12, 14, and 15 ALSEPs) was designed to measure high-energy radiation damage to three solar cells, to measure reduced solar cell output due to dust accumulation, and to measure reflected infrared energy and temperatures for use in computing lunar surface temperatures. The data held at the NSSDC from Apollos 14 and 15 is in the form of plots on microfilm showing temperatures and solar cell output over time.
The Alpha Particle Spectrometer carried on the Apollo 15 and 16 Command and Service Modules consisted of an array of silicon surface barrier detectors that measured alpha particles in the energy range 4.5 to 9.0 MeV from orbit. The data can be used to identify localized sources of enhanced radon emission that may correspond to regions of enhanced lunar outgassing. The data are on magnetic tape in IBM 360 format.
The Far Ultraviolet Spectrometer on Apollo 17 was an Ebert-Fastie spectrometer, which measured the radiation intensity as a function of wavelength from 1180 to 1680 Angstroms. It was used to collect data on Earth UV emissions (as well as UV emissions from other sources) from orbit on the Apollo 17 Command Module. The data consist of counts of photoelectrons and wavelength intervals on magnetic tape written on an IBM 7094 computer and plots of the data on microfilm.
The Passive Seismic Experiments on Apollos 12, 14, 15, and 16 consisted of triaxial, orthogonal seismometers as part of each ALSEP station. These could record ground motion due to moonquakes, meteorite and spacecraft impacts, and tidal deformation. The data are held as compressed event records on magnetic tape and microfilm.
Another potential source of valuable information resides in the ALSEP Work Tapes. These data are the actual telemetry stream from the ALSEP stations, which include housekeeping and engineering data on the condition of the ALSEP central station as well as the various experiments. This data, which is digital but is not in an easily usable format, would provide pertinent data on the day-to-day operation of equipment on the lunar surface and the long-term effects of the lunar environment on equipment. It can also provide data for periods from which data are not available from several experiments.
A detailed list of the data sets chosen for restoration is shown in Table 2, including estimates of the relative effort involved in restoring the data sets and the priority assigned to their restoration based on the recommendations of the Lunar Data Evaluation Team.
More detailed descriptions of the experiments and data sets are available online at http://nssdc.gsfc.nasa.gov/planetary/lunar/lunar_data/lunar_data.html .
Table 2 – Apollo Lunar Data Sets Recommended for Restoration. Lunar data is held on a variety of media at the NSSDC. The expected degree of effort to make these data available and the priority assigned to each are shown.
Lunar Data
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Media
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Priority
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Effort
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Apollo Mission
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SIDE Mass Analyzer
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Mag. Tapes
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High
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Low
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12, 14, 15
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SIDE Total Ion Energy
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Mag. Tapes
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High
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Low
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12, 14, 15
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Charged Particle Environment
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Mag. Tapes
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High
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Low
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14
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Solar Wind Spectrometer
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Mag. Tapes
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High
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Low
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12, 15
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Cold Cathode Ion Gauge
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Microfilm
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High
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Medium
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14, 15
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Subsatellite Lunar Part.
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Mag. Tapes
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Medium
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Low
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15, 16
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SIDE PI Raw Data
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Mag. Tapes
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Medium
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Medium
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12, 14, 15
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SIDE Hard Copy Plots
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Hard Copy
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Medium
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Medium
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12, 14, 15
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Soil Mechanics
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Microfilm
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Medium
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Medium
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15, 16
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Dust Detector
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Microfilm
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Medium
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High
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12, 14, 15
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ALSEP Work Tapes
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Mag. Tapes
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Medium
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Medium
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12, 14, 15, 16, 17
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Alpha Particle Spectrometer
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Mag. Tapes
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Low
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Low
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15, 16
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Far UV Spectrometer
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Mag. Tapes
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Low
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Low
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17
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Lunar Passive Seismic
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Mag. Tapes
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Low
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High
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12, 14, 15, 16
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Apollo Panoramic Camera
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Film
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Low
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High
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15, 16, 17
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Photographic Data
Of the numerous diverse lunar photographic data sets archived at the NSSDC, the Apollo panoramic photography was chosen because of its high resolution and coverage of potential landing sites. The panoramic camera flew on Apollos 15, 16, and 17 and covered a wide swath of the lunar equatorial region at a resolution of 2 to 5 meters. The set exists as photographic hardcopy, as 5” x 48” first generation positive frames on roll film (Figure 5). The NSSDC is digitizing the Apollo Hasselblad photography taken from orbit and Lunar Orbiter photography is currently being digitized by the Astrogeology Branch of the U.S.G.S. in Flagstaff, Arizona. Both these sets should also prove useful for lunar surface analysis. More detail on the photographic products held at the NSSDC is available at: http://nssdc.gsfc.nasa.gov/planetary/lunar/lunar_data/lunar_data_photo.html .
Figure 5 - The Apollo panoramic cameras imaged the Moon at up to two meter resolution, much higher than the Clementine UV/Visible camera (inset), providing detailed views of the lunar surface.
2.5 Other Data
The NSSDC has a set of CDs from a JPL data preservation effort. The CDs hold direct copies of 7-track Apollo project tapes. Relevant data may be contained on these CDs. As the data was only copied for preservation purposes it has not been analyzed. We hope to be able to identify other data not currently held at the NSSDC to add to this effort. This includes later time-period data from some of the experiments which have been identified but never received at the NSSDC, data mentioned in published reports which were not archived, and higher resolution data which were never submitted. For example, the NSSDC has no data archived from the Apollo 16 and 17 Cosmic Ray Detectors, but does hold copies of published reports on the data. There is some raw format data at NSSDC, which may require the assistance of the investigators involved in the experiment (one of whom is on the NSSDC staff) to put into useful form quickly. The NSSDC has only a small amount of data from Soviet lunar missions. As part of this effort we hope to identify and retrieve more Soviet lunar data, specifically data and information from Soviet rover and sample return missions in the 1970’s, which would prove useful for mission planning. This will be accomplished by sending Natasha Papitashvili, an NSSDC scientist born and raised in Russia, to meet face to face with Russian Program Scientists to gather information. We will also ask for community input on any other data sets, which may be relevant to lunar exploration but have not been identified at the NSSDC and are held elsewhere.
3.0 Technical Approach
3.1 Tasks
As discussed in the background section the data evaluation panel has ranked the NSSDC uniquely held data for their potential importance to the President’s new initiative. From this analysis this proposal requests funding to support the following steps:
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Reformat older digital data into modern formats useful with current scientific data analysis systems
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Scan, OCR and/or key in data held on microfilm and verify
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Digitize the extensive pertinent film products
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Enhance the metadata for each of these data sets (including bibliographic references)
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Implement a new database (LEED) and web site providing rapid access to the metadata and data
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Provide the data and metadata to PDS in the appropriate format
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Hold periodic science panel reviews of progress and improvements to the system
The NSSDC has all the resources for this endeavor in terms of personnel experienced in all aspects of preserving and archiving data and most of the necessary equipment. We have a history of success managing data migration and preservation efforts similar to this task. As mentioned earlier, the NSSDC is the largest repository of this lunar data already.
3.2 Magnetic Tapes
The NSSDC has the necessary equipment to read and transfer data from 7- and 9-track magnetic tapes. The data will have to be translated from older formats to an acceptable modern format. We have experience in migrating and restoring data from older tapes and formats here at the NSSDC. NSSDC staff members are currently engaged in a separate project to migrate offline magnetic tape data sets to online or near-line, and to also convert their paper documentation to online PDF files (with scanned images of the paper pages) that can be read or printed by a user. The project is almost finished with the detailed operational planning needed to make this process as much automated and script-driven as possible. The initial list of data sets to be migrated contains about 500 data sets, but only two of them are lunar data sets. If this proposal is funded, we will move the appropriate lunar data sets to the top of the list of data sets to be migrated. Thus the lunar data restoration can benefit from our on-going archive operations.
Quality control plans are included in all phases, from setting up to read the tape files to ensuring that all PDF documentation is complete and suitably legible for the online user. All of the information needed to ensure long-term preservation and use of the data is contained in Archival Information Packages (AIPs*, following the OAIS** model), which are generated and ingested into the archive in a semi-automated fashion, and at the same time the data files and documentation PDFs are put onto the FTP server.
The details needed for tape reading, such as block size, record size, and method used in converting from 7-track to 9-track tape (for some data sets), are obtained from the documentation and entered into a database, so that they can be automatically compared with what is found by a special program that reads the tapes and stages them to magnetic disk. If a discrepancy is found, an error message is generated. Manual intervention is needed before processing of that data file proceeds, but the automated flow can continue with tape files that are properly readable. In addition, a short dump is generated for the first tape in a data set, so that it can be manually checked later to verify that the indicated format description is correct and that the internal machine representation of numbers is as specified. Our staff members are experts and have years of experience in tape operations, which is becoming a lost art as computer operations rapidly move away from use of these tapes. In fact, these tape drives are no longer being manufactured, so we must migrate these data sets while we can still read them with our existing drives.
3.3 Microfilm/Microfiche
Lunar data available only on microfilm or microfiche (Figure 6) can be read using existing equipment at NSSDC. Data which are in the form of graphs or plots will be photographed and a set of digital images created. Data that is in the form of tables or listings of numbers will first be converted to a digital image, and then may have to be keyed in manually. Our experience (see below) has shown that optical character recognition (OCR) will not work on this data, as the quality is poor and a large proportion of the characters cannot be recognized by the software. Given the difficulty of digitizing data directly from microfilm or microfiche, we will make every effort to identify digital
versions of any of this data held elsewhere.A similar effort was made to preserve and digitize data from the Viking 1 and 2 Lander Labeled Release Biology Experiments in
* The Archival Information Package (AIP) is a conceptual component of the information model that is part of the OAIS Reference Model Standard. Within that model, there are several types of Information Packages and the AIP is the Information Package that is actually stored by the Archive. Each Information Package is composed of four Information Objects - a Content Information Object, a Preservation Description Information Object, a Packaging Information Object and a Descriptive Information Object. The AIP contains sufficient information in each of these objects to ensure the long-term preservation of the data enclosed in the package.
** The Reference Model for an Open Archival Information System (OAIS) is a Consultative Committee for Space Data Systems (CCSDS) and an ISO Standard. The OAIS Reference Model is a conceptual framework for a digital archiving system. It provides a shared set of archive related concepts and terminology, details the common archive functions, and supplies a generic information model.
2001. The full data were only available on microfilm and a subset of the data were on computer printouts. The data were in the form of listings of the instrument and housekeeping readouts over time. Neither the microfilm nor the printouts were in a form which could be scanned and successfully digitized with optical character recognition. The only solution was to manually read and type in the data. This was done at the NSSDC and Washington University at St. Louis. The data were checked for errors, validated, and had all relevant metadata added before being converted into PDS format. The data then underwent peer review before being validated and made available to the research community. The outcome was a renewed interest in the scientific literature on the possibility of detection of life on Mars by the Viking Lander biology experiments (e.g. Levin, G. V., Icarus, 159, 266-267, 2002; Miller et al., Proceedings SPIE, 4495, 96-107, 2002). We would draw on this experience in our digitization of microfilm and microfiche lunar data sets. The full data set is available online at: http://nssdc.gsfc.nasa.gov/database/MasterCatalog?ds=PSBI-00001
Figure 6 – The NSSDC holds data in a large variety of formats, including much older data on 7- and 9- track magnetic tapes and microfiche.
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Photographs
We have performed a system engineering study to determine the best digitizing process for our lunar photographic data. Table 3 summarizes the results. The best option for this work would be to use a large format camera on a copy stand. Some of the equipment for this already exists at the NSSDC, the remainder of the set up, including software, would cost about $15,000. The image size can be adjusted to give resolutions of 0.5 to 1.5 kpi (kilopixels per inch) for full images, to the optimal 5 kpi by zooming into portions of the image. The portions can be mosaicked together digitally so the full image can be made
available at full resolution. The lower resolution cameras are not as cost effective
because more frames would have to be mosaicked together after the imaging than for the
higher resolution camera to achieve the same kpi. The panoramic film can be left on the reels and moved over a light stand for imaging. This method also has the advantage of very fast turnaround, less than 20 minutes per full image and the versatility to handle the different format shapes. Using this option, the entire collection can be digitized at about 1.2 kpi in five to six months. The size of the full resolution images (roughly 6 gigabytes) makes digitizing all the images at full resolution impractical. Digitizing them at 1.2 kpi gives images sizes of about 350 Mbytes. Selected images can them be digitized at full resolution on demand.
Table 3 – Photographic Digitization Options. A camera with copy stand is the most efficient and economical method to digitize the Apollo panoramic photographs held at the NSSDC.
Options
|
|
Maximum Instrument Resolution
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Average Resolution (5”x 6”)
|
Time per 1
kpi Frame
|
Total Cost
|
Camera
w/Copy Stand
|
SLR 35
|
4.5 x 3 kpi
|
0.6 kpi
|
25 min
|
$60 K
|
Medium Format
|
5.3 x 4 kpi
|
0.8 kpi
|
20 min
|
$55 K
|
Large Format
|
8 x 6 kpi
|
1.2 kpi
|
15 min
|
$50 K
|
Outsourced
|
|
0.3 to 10 kpi
|
10 kpi
|
|
$200 to $350 K
|
Flatbed Scanning
|
Aerial Scanner
|
10 x 10 kpi
|
10 kpi
|
10 to 15 min
|
$60 to $70 K
|
Tabloid Scanner
|
5 x 5 kpi
|
5 kpi
|
20 min
|
$60 K
|
Present Scanner
|
1.6 x 1.1 kpi
|
1.1 kpi
|
20 to 30 min
|
$40 to $55 K
|
Drum Scanning
|
|
1 to 20 kpi
|
20 kpi
|
30 min
|
$110 to $130 K
|
The Apollo panoramic photography is held on rolls of film, each frame is 5 x 48 inches in size, so these may have to be digitized in pieces with large overlaps. The expertise and experience to digitize photography exists at the NSSDC. However, we did look into outsourcing the scanning to a commercial concern. This would be prohibitively expensive; the large and unusual frame sizes resulted in estimates of $200,000 to
$350,000 to scan the roughly 4500 photographs identified. Flatbed scanning of the images here at NSSDC could be done. With our current equipment we could only achieve a resolution of 1.1 kpi and we would have to cut the panoramic film. Given the resolution of the photography approximately 5 kpi would be necessary for full resolution scans. Flatbed scanning would take roughly 20 to 30 minutes per image. Aerial scanners exist, which are built to scan rolls of film and would be ideal for the panoramic film, but these scanners cost between $50,000 and $60,000. These would take about 15 minutes per image but can be automated to run scans and move film with minimal operator attention. The resolution of aerial scanners can be up to 10 kpi. Good quality drum scanners which can handle our images cost about $60,000 to $80,000 and can give resolution up to 20 kpi, but they are not easy to use and require more time per image than the other options. They would also require us to cut the panoramic film.
3.5 Online Availability
All restored and digitized data will be stored in a database (LEED) and made available online via a web-based information system at NSSDC. The data will include all metadata and documentation necessary for analysis and access to our extensive bibliographic database, which currently holds about 2000 references to lunar data. Other, already digital lunar data from Clementine and Lunar Prospector will be included in the LEED as well. A search capability with multiple pathways to the data will be available, including a graphical browse capability using plots of the data. Specifically, the data will be put into CDF (Common Data Format) and included in NSSDC’s CDAWeb system (http://cdaweb.gsfc.nasa.gov/), which will also allow correlative studies with other satellite data sets. This system will make the data readily available and useful to mission planners and engineers.
3.6 PDS format
The final step will be to put all data in PDS format and have the data sets peer-reviewed and validated by the PDS. PDS data sets are self-describing data archives, all data have descriptive labels and catalog files explaining the data and formats. Ancillary information in the form of digital documents describing the data, experiment, and mission, as well as the processing history, indexes to the data, pertinent references, contact information, and errata files is also included. We have had preliminary discussions with PDS personnel about this effort. We also note that the new head of NSSDC, Ed Grayzeck, has long experience with the PDS as Archive Manager of the Small Bodies Node at the University of Maryland and will assist in this endeavor. This will assure the widest possible community access to the data.
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