The long road to ALSEP data recovery

The human presence on the Moon did not end with Gene Cernan’s final footsteps, nor with Jack Schmitt’s final words before the Apollo 17 lunar module launched from the lunar surface on December 14th, 1972. The remnants of the six Apollo endeavors will, of course, remain on the lunar surface indefinitely as monuments of 20th Century space exploration. But for five years after Apollo 17, a human presence on the Moon was maintained through a collection of experiments at each landing site called the ALSEP program.

ALSEP lunar mass spec
Down-Sun picture of the Lunar Mass Spectrometer with the main hub and antenna in the background. (Image from the Apollo Lunar Surface Journal)

Over 5000 ARCSAV tapes were produced during the years of ALSEP data collection, and today most of these are missing

When the Apollo Lunar Surface Experiments Package (ALSEP) program was terminated on September 30th, 1977, it brought an end to 8 years of continuous data collection on a planetary body – a record that would stand (I believe) until Opportunity rolled past 3000 sols in 2012. And, much like Opportunity, ALSEP experiments long outlived their nominal one-year lifetimes. The ALSEP program relayed real-time data on seismicity (natural and astronaut-made), solar wind strength, ion flux, shallow surface heat flow and more to the distributed Manned Space Flight Network on Earth. Analog magnetic tapes (14-track range tapes) from the distributed network were collected at the Johnson Space Center (JSC) for further processing and re-recording. Range tapes made between November 1969 and February 1973 were to be permanently archived at Goddard Space Flight Center. Between 1973 and February 1976, a day’s worth of data from each site were stored onto separate magnetic tapes (7-track digital ARCSAV tapes) so range tapes could be recycled. Data processing was moved offsite (1976-1977) to the University of Texas, where the use of ARCSAV tapes were replaced by 9-track digital tapes (work tapes). And throughout this eight year period, numerous tapes were made for preliminary reports by PIs (PI tapes). Well over 5000 ARCSAV tapes were produced during the years of ALSEP data collection, and today most of these are missing.

SDS Sigma 7 tapes
In fact, if this tape rack represented the entirety of the ALSEP data collection, we would only have about three tapes (Image by fastlizard4 on Flickr)

The extended-mission life of ALSEP operations created some unanticipated issues for PIs. For example, the six passive seismic experiments recorded data 24-hours a day, enough to fill over one thousand range tapes per year for each site. The ever-growing volume of data tapes were increasingly difficult for PIs to work with, though this was abated somewhat by transferring to higher data-density tapes. The sharp decline in post-Apollo funding – NASA’s budget dropped by a third in the 1970’s – meant some PIs could not devote the hours necessary for data processing and maintenance. Although PIs were instructed to archive tapes with the Washington National Record Center (WNRC), the requirements were vague and poorly enforced and so only an estimated 50% of the PI data were archived. In some cases this was only a subset of processed, “scientifically important” data as selected by PI teams.

Records show something like 3270 ARCSAV tapes made between April 1973 to February 1976 were sent to WNRC. Records also show a massive withdrawal of analog tapes from WNRC, prompted by the tape shortage in 1980, which included ~2800 ARCSAV tapes as Goddard Space Flight Center staff searched high and low for reusable/recyclable tapes. Fortunately, the 7-track digital tapes were not their target (the Apollo 11 landing footage tapes were probably not as fortunate), but instead of returning them to WNRC the ARCSAV tapes were stored in the basement of GSFC. Many of these were later destroyed in a 1990 building flood, and the trail of surviving tapes goes cold after they were removed from the basement of GSFC during cleanup.

Modern computers could do so much more with the ALSEP tapes than was previously possible, if only the data were available. The potential was highlighted in the 1990’s when the University of Texas ’76-’77 tapes were reprocessed and made available on the National Space Science Data Center. But a concerted effort to find the missing tapes wouldn’t get off the ground until 2004, when the presidential mandate for space exploration sparked a resurgence in lunar research in terms of both interest and funds. With practically zero ground-truth characterization of the lunar surface (apart from returned samples and meteorites) and lunar atmosphere, the ALSEP program was a natural target for reevaluation. Suddenly there was a call for these tapes that were nowhere to be found. The NLSI Recovery of Missing Data Focus Group was formally convened in 2007 and is a multi-institutional, (mostly) volunteer-run effort led by some of the original ALSEP PIs.

ALSEP dust detector data tape
Apollo 12 dust detector PI tape of days 465-468 (Source: Prof. Brian J. O’Brien PI and SpectrumData)

It is through the efforts of the ALSEP focus group that most of what we know of the tapes has come to light. Every year at the Lunar & Planetary Science Forum (in March) and Lunar Science Forum (in July), the group has a side meeting where they share their successes and frustrations. And there have been successes. In 2010, ~450 ARCSAV tapes made between April and June of 1975 were recovered from WNRC. And at some point, a large quantity of ALSEP data was condensed onto microfiche and microfilm, and also backed up on paper. For LPSC this year, an abstract from the group announced the complete restoration of seven lunar data sets. Another eight data sets are in the final stages and will likely be completed by LPSC, with a promise of more to come. In short, many raw data tapes have been recovered…and also some processed data tapes, and reprocessed tapes of processed data tapes, and prints of raw and processed data…now what?

Hopefully “restoration” should hint at something more involved than slapping an ARCSAV tape in a reader and ripping it onto a hard drive like a CD. Well…OK, that is part of it. But unsurprisingly, such tape readers in working condition are increasingly rare, and at least some of the ARCSAV data recovery was outsourced to data recovery/conversion companies or citizens. Prof. Brian J. O’Brien (Australian government) was an original PI for the Early Apollo Surface Experiments Package (EASEP) and ALSEP Dust Detectors (Apollo 11, 12, 14, and 15) and the Charged Particle Lunar Environment experiment (Apollo 14). He maintained possession of a number of original tapes (including the one pictured above), and is working with SpectrumData to recover quality data.

And quality is the other main issue here. Tape quality degrades over time. Converting tape formats can introduce transcription errors. Processed data might be missing metadata on conversion programs, units, calibrations, random transcription errors, or whatever “corrections” the PI deemed necessary. Even in raw data tapes, anomalies occasionally occur because, after all, they came from the Moon.

It's all the way past those trees and everything.
It’s all the way past those trees and everything. (Photo by poikiloblastic)

Without relevant metadata (including telemetry to assess transmission quality), the tapes would be worse than useless because any product would rest on a flawed foundation. That remains a major obstacle to data restoration. Significant progress in terms of tapes acquired and metadata resolved has been via cooperation with PI teams and their universities, with one PI even lending an ALSEP experiment notebook to scan for use in calibrating a data set. Prior to archiving with the Planetary Data System, data sets undergo peer review. The ALSEP-recovered-data-related abstracts submitted to LPSC this year are a promising sign of the science return we can expect to see from these important datasets in the years to come.


Almost all of the details above are collected from focus group meetings at the NLSI Lunar Science Forum (2011 & 2012), as well as ALSEP Data Recovery Focus Group progress abstracts submitted to the Lunar and Planetary Science Conference (2011 & 2013). My contribution to the focus group thus far has been to introduce myself at the beginning of said meetings.

ALSEP system and experiment reports are available from the LPI website.

Recovered EASEP and ALSEP data sets are archived in the Planetary Data System Geoscience Node.

Related: Lunar Orbiter Image Recovery Program (LOIRP)


Restructuring NASA Lunar Science

Resources are not infinite, and the 2013 administrative budget will call for a significant cut to planetary sciences. This is causing a stir (to put it mildly) in the planetary community and has left many organizations scrambling for a plan. For example, the Mars Program Planning Group (MPPG) presented their final report this week, summarized here by Casey Dreier. Essentially, the proposed cuts severely limits the potential of future Mars missions, and once again Mars sample return is at least a decade away. You can read Casey’s post for the latest on the Mars program, but it’s a similar story across the board and has been for many years. Visit the Planetary Society for the latest on how the community is responding and how you can help. NASA calls for promising returns but winds up in trouble either by underfunding programs (see: the Constellation program) or allowing budgetary overruns at the detriment to other programs. Many missions are pulled off within their proposed budgets (like the Moon’s GRAIL mission and the Juno probe), but overruns are often joked about as being standard operating procedure.

Despite the challenges, we keep reaching out beyond low earth orbit. “50 Years of Space Exploration” via National Geographic (image linked to source).

As the momentum of the Apollo missions began to wane in the eighties, the lunar community also started to shrink. Papers published from the Proceedings of the Lunar and Planetary Science Conference (LPSC) saw fewer lunar papers as the Apollo-era scientists started to leave the field – and of course at the same time other areas of planetary science were growing. Funding for lunar research lessened and many researchers followed the money to Mars (and elsewhere). In some years, the week-long LPSC would host only a couple lunar sessions (of 35+ total sessions). The most recent LPSC had 6 lunar-specific sessions, and of course there is significant overlap with broader session topics like Impact Craters and Airless Bodies. In addition, right now several satellites are further characterizing our nearest neighbor and keeping the Moon in the science spotlight.

Facilitating the Moon’s resurgence is the NASA Lunar Science Institute (NLSI), a virtual institution and primary hub of lunar research. Established in March 2008, NLSI is comprised of a small home base at NASA Ames and several US teams and international partners. They host the annual Lunar Science Forum at NASA Ames (the 5th annual NLSI Lunar Science Forum was recently held in July). Each year the Forum is bigger and better-attended, packed with three full days of lunar science. The institute has been key in rebuilding and strengthening ties in the lunar community, but that seems set to change.

NASA recently put out a call for comments on soon-to-be-released Cooperative Announcement NNH12ZDA013J (CAN). The call for comments are to deal with high-level features of a proposed virtual institute to be jointly supported by NASA Science Mission Directorate (SMD) and Human Exploration and Operation Missions Directorate (HEOMD).  A selection from the Addendum about the scope of the CAN:

The research scope for the planned CAN will be in the fields of lunar, NEA and Martian moons sciences, with preference given to topics that relate to the joint interests of both planetary science and human exploration.

This new Institute will replace the NLSI and expand its role to include near earth asteroids (NEAs) and Martian moons (Phobos and Deimos). There are a number of current organizations I assume will be part of or partnered with the new Institute, as their goals overlap. This includes the MPPG as mentioned above, the Small Bodies Assessment Group (SBAG), the Lunar Exploration and Analysis Group (LEAG), and the Center for Lunar Science and Exploration (CLSE), the Next Generation Lunar Scientists and Engineers (NGLSE) group, and the Lunar Graduate Conference (LunGradCon). While the MPPG, SBAG and LEAG are independent planning groups which I think will remain intact, I am not as certain about the effects this new Institute will have on the CLSE, NGLSE and LunGradCon. Holy crap that is a lot of acronyms.

NASA loves acronyms. They have a whole search engine devoted to searching through 14198 acronyms, which does not include many mission and organization names (click image for page).

The CLSE is also a primarily virtual institute (I think), but is organized by the Lunar and Planetary Institute (LPI) and the Johnson Space Center (JSC) in Houston, TX. The CLSE states they state they are an “integral part” of NLSI, so perhaps CLSE will become the sole lunar-specific virtual institute.

NGLSE I believe has independent funding from but arose in partnership with NLSI. There is always a one-day NGLSE workshop held the day prior to the start of the NLSI Lunar Science Forum. Noah Petro, part of the NGLSE executive committee, has a very broad definition of “next-gen” which encompasses anyone who entered the lunar field post-Apollo.

LunGradCon is held the weekend before the NLSI Lunar Science Forum (typically a one-day conference on Sunday), and is run by graduate students for graduate students (and some post-docs). As a participant and member of the organizing committee, I am totally unbiased when I say it is a great opportunity to network with those new to the field of lunar research and see what the community is working on. The LunGradCon organizing committee will have to figure out (with input from other graduate students) how to adapt to this new community.

There are a couple of other points in the CAN that are worth mentioning. I wrote above that the new Institute will expand the role of NLSI, but not that it will expand its size. During the recent Forum there was much discussion about the future of NLSI, and whether there would be future Lunar Science Forums. The diplomatic answer from Greg Schmidt was that there would definitely be another Forum at NASA Ames, but he never specified Lunar Forum. What I see happening is a defocusing of the Institute that mirrors the defocusing of NASAs exploration strategy from Moon First to Flexible Path. I started this article with discussion of funding because I think the current status of NASA’s budget is a large player in why this change is occurring. In regards to the research scope of the Institute, the addendum is not very exclusive:

Additionally, while the topics of the planned CAN focus on potential destinations for human exploration (the Moon, NEAs, Phobos and Deimos), these topics can sometimes best be considered within the broader context of comparative planetology. Therefore, innovative proposals that include comparisons with main belt asteroids, comets, Mercury, Venus and Mars would be appropriate. Similarly, studies of telerobotic operational sites and associated research potential, including Earth-Moon Lagrange Points and the moons of Mars, may also be appropriate as part of a larger scientific effort.

There is no foreseeable future where Venus, Mercury, or comets will be targets of human exploration, but their inclusion leaves the door open to further defocusing of the Institute. In addition, Mars is unique and already has its own NASA funded program and plan for human and robotic exploration. Large sample return from Mars and the Moon are feasible if funded, and the success of Hayabusa showed we can actually get something from asteroids. OSIRIS-REx will hopefully continue that trend (with a potential return next decade).

This CAN is asking for comments on the “high-level operations” of the proposed Institute, so I believe it is an inevitability that NLSI will be replaced. Note that the interpretations and opinions I’ve talked about are my own, and both them and the CAN are subject to change. I am concerned about the connections the lunar community has built in the past few years, and am worried it will once again start to fade. Worried, but not closed to the idea of this new Institute. There is much potential here, and I do see value in collaboration between groups studying these airless bodies. However, I attend both the Lunar and Planetary Science Conference and the NLSI Lunar Science Forum, and I have benefited greatly from both. LPSC is a huge, week-long conference with four simultaneous sessions going on throughout the day, making it impossible to see everything. The Forum is a much more intimate setting with my immediate peers in the lunar community, and I can see that being lost in the incorporation of new solar system bodies.