From first principles, design a fully autonomous, scalable, and economically self-sustaining system for planetary defense against near-earth objects (NEOs) between 50 and 500 meters in diameter.
Constraints and Requirements:
- Detection & Tracking: Your system cannot rely solely on Earth-based observatories. It must include a space-based detection and tracking component (e.g., a constellation of satellites in various orbits) capable of identifying and calculating the trajectory of threatening NEOs with at least 5 years of lead time for a 150-meter object.
- Interception: You must design a primary interception vehicle/method. Kinetic impactors are an option, but you must solve for the terminal guidance problem to ensure precise impact. Also, design a secondary or follow-up method (e.g., a “gravity tractor” or laser ablation system) to make fine adjustments to the post-impact trajectory or to handle fractured objects. The system must be deployable from a standby orbit to an intercept trajectory within 30 days.
- Economic Self-Sustenance (The Core Challenge): The system cannot be a pure cost center funded by governments. Design a mechanism for it to generate revenue. This must involve in-situ resource utilization (ISRU). Your interceptor vehicles, after a kinetic impact mission, must have a secondary function. For example, a “shepherd” drone that follows the main impactor could be designed to autonomously rendezvous with the now-neutralized (or other non-threatening) asteroid, mine it for valuable materials (e.g., water ice, platinum-group metals), and process them in-space.
- Propulsion & Logistics: The entire system must rely on propellant that can be, at least in part, sourced and refined in space (e.g., from water ice on asteroids or the Moon) to enable rapid and repeated deployment without costly Earth launches for every mission. You need to architect the logistics of how you would refuel your interceptor fleet in orbit.
- Scalability: The architecture must be scalable. How does your system go from handling one potential impact threat every decade to handling multiple threats per year as detection capabilities improve? Your economic model must scale with your operational tempo. What is the business case for building the 100th interceptor/miner versus the first?
Solve for the optimal design of the detection constellation, the interceptor/miner vehicle, the in-space refining process, and the overall business model that makes planetary defense profitable, and therefore, robust and enduring.
