Technical Dispatches, as related by the team behind Karman+, are intended to bring readers behind the scenes and into the research. In this edition, Lisa, a Mission Design Engineer with a background in Guidance, Navigation and Control shares a glimpse into our trajectory design collaboration and philosophy.
I joined Karman+ early last year with the goal of helping define the spacecraft architecture and requirements in the context of our mission objectives: to mine Near-Earth Asteroids (NEAs) and do that in an iterative and scalable manner. My background as a Guidance, Navigation and Control (GNC) Engineer means I particularly enjoy trajectory design and the process of determining how we can reach our desired targets. That has been my focus this past year, but I’ve found (to my delight) that there is so much more to this job. One of the aspects I find most enjoyable is the collaboration and the way Karman+ values and incorporates knowledge from a wealth of sources. I decided to join the Karman+ mission as I find the topic of asteroid exploration and mining fascinating but I also felt like I could really benefit from a change in perspective. I have spent time at larger agencies and companies but have always been curious about the startup world. The space industry as a whole is changing and the growth of New Space and companies such as Karman+ shows us that a different approach is not only possible, but necessary for innovation. Agencies will always be the backbone of the space ecosystem, but the commercial sector will continue to become more prominent and act as a catalyst. I am interested in how we can draw on both sectors to achieve our collective goals.
Consider this: Once solely the playground of large government agencies, ambitious space missions are now being jointly, or sometimes entirely, driven by the commercial space sector. These advances make endeavors such as asteroid mining not only technically feasible, but an economically viable business. Only a handful of agency-led missions have demonstrated asteroid exploration — and in three cases — a sample return to Earth. Whilst this is a promising start, private companies such as Karman+ will have to take the lead in ensuring large-scale mining operations become a reality.
Once solely the playground of large government agencies, ambitious space missions are now being jointly, or sometimes entirely, driven by the commercial space sector
There have been a number of paradigm shifts within the space industry in recent years which have enabled ambitious low-cost missions and helped foster growth of the space economy. We have seen a boom in private companies, and in particular, very large growth in the small satellite market due to falling launch costs and increased availability of components and platforms. However, only a few of these missions have been to deep space and there is still uncertainty about how reliable these systems are in those tougher environments and over a longer lifetime. These small, lower-cost developments are unable to accommodate the level of redundancy typically found in traditional agency missions, due to both physical and resource constraints. However, these design trade-offs and their associated risk must be well understood and accepted in order to make rapid progress. At Karman+, we believe we can strike that balance by learning from those larger agency missions and paying due diligence to those rigorous design processes but also be able to accept a different level of risk based on our mission parameters, and therefore adapt those processes accordingly. By tolerating risk, we allow ourselves to achieve faster iteration which ultimately gives us the space to learn quickly, and even to think about key problems entirely differently.
Sample Return (Science + Research) VS. Mining (Commercial)
Asteroid mining has featured highly in both academic literature and popular media, but there have only been a few missions that have returned material from an extra-terrestrial body. The first were those returned during the Apollo program and manually collected by astronauts from the lunar surface. In 2020, China’s Chang’e-5 mission returned the first lunar samples since the 1970s, this time from an unmanned mission.
We also have gained invaluable insight into asteroid bodies from a number of inspiring missions. The Hayabusa-2 spacecraft developed by JAXA returned a ~5g sample from Ryugu in 2020. More recently, NASA’s OSIRIS-REx mission — due to return to Earth in 2023 — collected a small amount of material (~0.6 – 2kg) from Bennu. Other asteroid missions such as DART and the soon-to-follow Hera mission will give us greater insight into these bodies, even despite the lack of sample collection. Undoubtedly there have been many technological advances since those first sample returns, yet arguably not much has changed in terms of the objectives: small-scale sample return for scientific analysis. This is where space-based mining differs.
Whereas all samples collected to date consist of less than one ton of material, a single space mining operation would have to be able to manage hundreds or even thousands of tons of material in order to make any profit in the hopes of sustaining a business. Although the topic of In-Situ-Resource-Utilization (ISRU) has long been studied and encouraged by various Governmental bodies and Space Agencies [1] [2], it is apparent that they will need to rely on commercial entities to really help drive those developments forward. In that sense, the notion of private vs. public funding can be misleading when in fact it takes strong collaboration and dedicated effort from both sides to establish such an ambitious long-term vision as part of the “New Space” industry [3].
A New Era
Thankfully there have been a number of recent shifts, driven by major technological advances within the space industry that are helping to improve the prospects for asteroid mining. The most notable are significantly lower launch costs thanks to reusable rockets (which are set to plummet further with the proliferation of launch systems like SpaceX’s Starship) and the extensive use of Commercial Off The Shelf (COTS) components. The miniaturization of critical components has also been a critical enabler for increasingly complex missions performed by small spacecraft, or CubeSats [4]. CubeSats are no longer confined to Low-Earth-Orbit (LEO) and have been flown to the Moon (CAPSTONE) and even beyond (LICIACube) [5]. Operational costs are also decreasing thanks to less mission and spacecraft complexity, along with the rise in autonomous systems. One of the reasons that CubeSats in deep space are now possible is the increasing number of small but powerful propulsion systems on the market. Stand-alone asteroid missions have not yet been achieved with a CubeSat, given the high Delta-V required, however, ESA’s M-ARGO mission is set to change that. One of my jobs as a Mission Design Engineer is to assess what type of propulsion is best suited to our spacecraft given our desired asteroid targets and their distance from Earth, but also in consideration of other spacecraft platform constraints (platform size, power, control authority etc.). All of these developments have a tremendous impact not only on our outlook, but what is achievable and sustainable in our future plans.
It is also important to not understate the limitations of these components and systems, especially given the very complex and hostile deep-space environment. Favorable asteroid mining targets have no atmosphere, with very high radiation that can damage electronics onboard. The temperature differences experienced by the spacecraft can also be very significant. Rapid, low-cost spacecraft development has become possible with heavy use of COTS components and platforms and whilst encouraging, we must not forget how and why they were designed. These spacecraft are generally not tested as extensively and have no real lifetime guarantee (certainly an issue when you might take a few years to even reach your asteroid target). Still they suggest possibilities that inform our work. The question becomes: How can we use this technology to our advantage whilst accepting and managing the associated risks? One of the ways we have approached this problem as a team is to perform ongoing reviews of technology capability and maturity. As part of that effort, my job is to regularly assess which available COTS components meet our mission and system requirements, and conversely, to determine which areas we need to spend extra resources on dedicated developments for our mission.
How can we use this technology to our advantage whilst accepting and managing the associated risks?
Iteration and Embracing Failure
Agencies have historically rested on the conviction that failure is not an option and have expended a lot of effort to demonstrate that the mission is completely fail-safe. While this is well-intentioned, especially for manned spaceflight, given the inherent unknowns and risks in space flight, even a near-flawless mission is extremely rare. Framing mission success around flawlessness may lead to inappropriate assessments of true risk, which can actually devalue the risk and be even more damaging. It’s also critical to view risk not only in the context of a single mission, but as part of an entire program. As such, there is a lot of wisdom to be gained from these anomalies or failures in a way that can actually reduce the overall risk. Otherwise, the fear of failure can stunt an organization’s ability to develop a program. Understandably, governments and agencies have a responsibility to minimize those risks wherever possible, but they are also increasingly focused on lower-cost, faster developments which are inherently more risky. In pursuit of speed and budget awareness, you have to also accept that the standard proven development processes no longer stand completely intact. The classical development approach is sequential, with each project milestone being met by conforming a number of requirements and standards. This can be a lengthy process which does not always facilitate rapid updates given the complex interdependencies within the development. Adoption of agile processes, as well as recognizing that these low-cost, smallsat developments are unable to meet all of the safety and testing requirements traditionally used as the milestone markers, means that the development schedule and cost can be greatly reduced [7]. For instance, ESA is working on tailoring its development standards (ECSS) [8] for smallsat missions to reflect this evolution in the sector. NASA is also moving in the same direction with its Discovery-class missions. Part of my role is likewise to understand which aspects of these standards are compulsory, recommended or perhaps not beneficial to us.
One of the most crucial aspects of establishing a large-scale asteroid mining operation is to not lose sight of the longer-term goals. For us, that means ensuring the spacecraft architecture and critical technologies we develop for our first mission translate to a large-scale operational phase. This is made possible by the ever-expanding COTS market and the increasing maturity and standardization of key technologies. This paradigm shift enables us to collaborate with the commercial space sector by using what has already been developed and ultimately, avoiding custom developments that are usually required for larger agency missions. This will allow us to focus our efforts on less mature technologies such as the extraction payload, that will have to be developed from scratch. The goal is to build an architecture that naturally lends itself to rapid iteration and scalability.
Determining the risk involved in these developments will always be a key aspect of any mission. It is critical that Karman+ remains conscious of the risk around us, mitigating it where possible, and working to understand what risks we are willing to accept in the name of progress. This is especially true for asteroid missions, as the majority of the NEO population is not well characterized due to the lack of observability. Previous asteroid missions also demonstrated unexpected results and emphasized the highly uncertain nature of these objects. We must also accept that no amount of preparation will give us all the answers we need to limit ALL of those risks pre-mission. In fact, we will learn the most useful lessons from interacting with asteroids. Our task is instead to determine what level of risk we can tolerate and how we can mitigate those whilst staying true to our spirit of innovation. We can do this with more conviction by adopting values from the commercial sector, via the growing availability of mature and cheaper technologies – and by drawing on valuable insights from agency exploration, via the rich heritage of the mission successes and failures.
Our task is to determine what level of risk we can tolerate and how we can mitigate those whilst staying true to our spirit of innovation
Looking Ahead
For Karman+, our success will rely on finding the balance between rigor and agility (see Technical Dispatch #0 on this matter). We understand that there are a lot of lessons to be learned from the missions that have flown, and of course, our asteroid mining predecessors who were sadly unable to make the vision a reality. There are many factors at play when it comes to establishing a viable space-mining business — some within our control and others beyond it. One certainty is that such a complex feat will never be accomplished by a single company or country but instead as part of a sustained and dedicated collaboration that is likely to endure and learn from some failures along the way. Only then can we Accelerate the Inevitable.
References
- ESA, ESA Space Resources Strategy [Accessed: 12 Jan, 2023]
- Tom Simon, Kurt Sacksteder, “NASA In-Situ Resource Utilization (ISRU) Development & Incorporation Plans”, Technology Exchange Conference, Galveston, TX, Nov 2007
- Will Lecky, “New Space and the Role of Public Support, v1.1”, May 2016, [Accessed: Jan 10, 2023]
- NASA, State-of-the-Art Small Spacecraft Technology 2021 [Accessed: 9 Jan, 2023]
- P. Tortora and V. Di Tana, “LICIACube, the Italian Witness of DART Impact on Didymos,” 2019 IEEE 5th International Workshop on Metrology for AeroSpace (MetroAeroSpace), 2019, pp. 314-317, doi: 10.1109/MetroAeroSpace.2019.8869672.
- Bryce and Space Technology. “SmallSat by the Numbers, 2021.” [Accessed: 12 Jan, 2023]
- Álvarez, J.M., Roibás-Millán, E. Agile methodologies applied to Integrated Concurrent Engineering for spacecraft design. Res Eng Design 32, 431–450 (2021)
- European Cooperation for Space Standardization (ECSS) [Accessed: 10 Jan, 2023]