“We Have Learned So Much Since Apollo”
During the week of January 8th of 2018 there was a marvelous “Lunar Science for Landed Missions” conference at NASA Ames (link here for the content of that conference). This was probably the best lunar science conference I have been to in a long time. Dr. Clive Neal from Notre Dame and Chair of the Lunar Exploration Analysis Group (LEAG) was one of the organizers, along with Greg Schmidt, deputy director of the Solar System Exploration Virtual Research Institute (SSERVI). Clive said in his opening at the conference that “we have learned so much since Apollo”. This is absolutely true. There have been some extremely high quality missions to the Moon, starting with the Clementine and Lunar Prospector missions in the 1990’s, but since the year 2000 a new generation of missions have accelerated the momentum, with 11 international missions (10 orbital and 1 landing) to our nearest neighbor in space. The conference reflected how the data gathered is building a gestalt for a new era of lunar science.
Exceptionally gratifying at the conference is the coming of age of a new generation of lunar scientists and researchers. There were many excellent presentations and many excellent discussions from the participants. Also participating was Apollo legend Dr. Harrison (Jack) Schmitt. One of the things interesting and gratifying was the acknowledgement of the value that Dr. Schmitt’s selenology (lunar geology) work on the Moon in Apollo 17. Since this was about lunar landed science, the point of the conference is what kind of science needs to be done on the Moon to build on the legacy of the Apollo missions, whether it be done robotically or by humans, either with in situ science or with sample return.
Since my own forte is lunar industrialization as well as lunar science, I found the presentations informative and not at all in conflict with that direction. Furthermore, the interest and willingness of the participants to consider that possible industrialization and science to not be inherently in conflict was gratifying. Indeed, after the conference it seems that a a renewed push to put humans on the moon will be dramatically beneficial to science and vice versa.
Following here I am excerpting some of the talk that Clive gave in opening the event. Again to praise the SSERVI crew, the videos and the slides and posters from the conference are already up and online and I strongly encourage everyone who is interested to take the time to peruse the information and watch the videos. I did not get to see everything I wanted to and thus this is great for review as well. All of the videos are directly linked from the agenda.
Clive started out with what has become obvious, we need more lunar samples.
It turns out, but not intentionally of course, that the Apollo missions did not land in the area that best represents the composition of the near side of the Moon. The Apollo samples are dominated by ejecta from the Procellarum KREEP Terrane (PKT; Figure 1), which is dominated by a unique selnochemical signature not seen over the rest of the Moon. The post Apollo remote sensing missions ( Clementine, Lunar Prospector, Lunar Reconnaissance Orbiter (LRO), Chandrayaan-1, Chang’E, Kaguya) have brought an avalanche of new data. Especially useful have been the instruments such as the LRO LROC high resolution imager (0.5 meter resolution visible light), the DIVINER radiometer experiment, LOLA laser altimeter, and the Mini RF radar experiment. These instruments coupled with the Moon Mineralology Mapper (M cubed) on Chandrayaan-1 have been a boon for lunar science and forms much of the input for the science presentations at the conference. The excellent analyses of the data by the lunar science community has brought us to the point to where the community has a well crafted set of questions that really need to be answered by the acquisition of new samples and in-situ research.
These snapshots from Clive’s presentation illustrates some of the richness of the data and the quality of the work being done.
These snapshots illustrate some of the areas of scientific inquiry that are important going forward for the sample missions. These areas are.
- Recent Volcanic Activity
- Pyroclastic Deposits
- Cratering Chronology
- Farside Highlands
- Permanently Shadowed Regions
All of these areas are congruent to the development of industrial activity and In Situ Resource Utilization (ISRU). It is the scientific exploration and understanding that allows those who are interested in industrialization to be able to be more specific with the execution of industrial development. It is from lunar samples and lunar remote sensing, filtered through the intellectual inquiry of the scientific community that enables industrialization to go forward and to be able to convince investors that what is claimed to be resources actually are there. It is then the industrialization community’s job to figure out how to make it happen. Here is where the two communities can work together to enhance and to enable the flourishing of science and industry and bring forth the true golden age of space.
The Virtuous Circle
During his presentation summation Clive put this chart up regarding the targets for lunar sample return and or in-situ exploration.
There are dozens of targets for sample return, far more than the summary that Clive has on his chart. These were not meant to be all-inclusive but to demonstrate the diversity of sites on the near and far sides of the Moon, as well as at the lunar poles. The important thing to be integrated into our thinking is that we need many missions to create a gestalt of understanding that allows to understand the formation, history, current state, and resource potential of our Moon. Additionally, many of these are apt precursors and companions for industrialization as well as subjects for scientific inquiry.
As most people know, the current administration has chosen to return to the Moon, and not simply the return to the Moon but to use it as a springboard for the economic development of the Solar System. During our last efforts in this area during the Bush era Vision for Space Exploration the community got bogged down in an argument regarding whether we needed a series of sortie missions or an outpost. The problem is that sortie missions, whether human missions, or robotic, are expensive. Sample return missions drive up the costs even more. Fortuitously, one of the foci of the return to the moon from the commercial world is lunar water production. Many in our community wax poetic about the value of this water for fuel depots and for delivering the water for Mars missions, for refueling satellites and for other off Moon applications. However, a more near term application of in-situ water is for the implementation of a global campaign to visit these dozens of scientifically interesting sites.
There are a multiplicity of reasons for doing it this way but here are a couple. The first is cost. The cost of a single sample return mission robotically will cost in excess of half a billion dollars and the sample size will be necessarily small, also due to cost. A community problem that this brings is that if we were to do it the way that we have in the past, there will be a request for proposals for a mission, lots of competition, and only one winner. Assuming that costs reduce over time a bit, there might be two teams that would win and a couple of sites would be sampled. Not only does this severely limit the science, it limits the development of the professional scientific community in this area.
Another reason is attached to something Clive noted in his presentation regarding theories related to cratering history in the entire inner Solar System. Our theories regarding inner solar system cratering rates over time, including Mercury and Mars are based upon and bounded by what we know about lunar cratering established by Apollo (and the Soviet Luna) samples and estimates of erosion rates on the Moon. Thus our knowledge is very loosely bounded in time and based on the very limited ground truth from Apollo and Luna. In order to effectively answer the question regarding lunar cratering age we need a much wider diversity of samples from craters of different presumed ages (based upon Apollo ground truth from returned samples). We simply are not going to be able to do this using the status quo way of doing things at NASA’s Science Mission Directorate (SMD).
Another reason is the effective use of assets. NASA’s Mars Opportunity and Spirit rovers landed on Mars in 2004. Opportunity is still operating there 13 years later. While the science is still interesting, what if that rover had been able to be refurbished and sent to another location on Mars (as an analog for this discussion regarding the Moon) of more scientific value. The next figure shows some of the locations and distances from the lunar north and south poles.
Conceive in your mind for a moment a rover with a suite of scientific instruments carried by a suborbital hopper that could take off from a lunar outpost, fly to a site of interest, carry out initial studies, and then return via its lander to the outpost before the end of the lunar day. Many of these missions could be carried out in parallel at low incremental expense with local water and a science platform with a wide variety of sensors. This would be a major force multiplier for pure science plus could be available for industry for selenological sampling by industrial interest for resource prospecting. Additionally, if there were communications satellites dedicated for lunar orbit these missions would come at almost no cost in terrestrial infrastructure. A relay satellite could use optical or high bandwidth RF communications back to the Earth, considerably relieving the NASA Deep Space Network’s operating burden and could provide an additional revenue source for a commercial relay communications satellite. Establishment of a lunar communications and navigation network was concluded by the workshop participates to be one of the early commercial “on-ramps” that would enable a robust lunar science and exploration program.
What Clive’s presentation and other ones at the conference illustrated beyond a shadow of a doubt that in emplacing a lunar outpost that has as an industrial goal of obtaining sufficient water for propellant, that this propellant would be exceptionally valuable to enable suborbital hops from the outpost to the various sites noted above for sample return and in situ study. The science benefits will be outstanding as well. Since there would be a logistical system in place for two way transit between the Moon and Earth samples could be sent back, examined, and new missions planned at a far more rapid pace than today. You simply can’t do this kind of science at Mars yet due to the long distances and cost of climbing out of the much deeper gravity well.
All of these things create a virtuous circle that is beneficial to science as well as to industry. Cost sharing, rapid mission tempo, commercial operations bringing the costs down, all act to dramatically enhance the science, which supports industry, which in turn provides a lot more opportunities for science. Today the Apollo samples are treated as the crown jewels of NASA, which in a sense they are, but the supplies are necessarily limited. Extending this through a robust scientific and industrial exploration and development program will be absolutely transformational for all concerned. This becomes an amazing test bed opportunity as well for operations that some in NASA have planned for the surface of Mars from Martian orbit.
Just the Beginning…..
Scenarios like the above are just the beginning of a golden age of planetary science. When I first started as a researcher in lunar science all we had was Lunar Orbiter, then Clementine and Lunar Prospector. It is the new generation of missions from Chandrayaan, Lunar Reconnaissance Orbiter, Chang’E that are just starting to open the door to science, bringing with it a new generation of researchers. The human return to the Moon to an outpost at the poles will have a dramatic potential to advance science in ways that have scarcely been imagined before because we have not considered what the melding of scientific and industrial interest can do to support each other.
Here on the Earth we have economic geologists as well as pure science geologists. It is inevitably going to go in this direction in planetary science as well, and this is a good thing as it will increase the cadre of trained scientists, bringing different perspectives and insights, which will support both science and the industrial sector. As we continue to move outward in the Solar System what we do on the Moon will serve as a template for the future. Our first tentative exploration steps over the last few decades is about to give way to an explosive era of activity that will bring benefits to all mankind………