Space Policy Edition #4: Near Earth Asteroids—Why we go, how we find them, and maybe mine them

Episode Summary

Executive Summary: The episode centers on asteroids as both scientific time capsules and potential threats, using OSIRIS-REx as a launch-point to discuss mission history, planetary defense, and emerging asteroid mining. The hosts trace NASA’s shift from neglecting small bodies to funding surveys, deflection planning, and increasingly ambitious asteroid missions, while also examining the legal and commercial challenges of private resource extraction in space.

Main Topics: OSIRIS-REx and New Frontiers-class asteroid exploration: The show opens with OSIRIS-REx as a medium-class NASA mission to Bennu, designed to return asteroid samples and deepen understanding of early solar system materials and near-Earth objects. NASA’s historical relationship with asteroids and comets: The hosts review the late start of U.S. asteroid/comet missions, the 1980s 'lost decade' of planetary science, and the rise of Discovery-class missions that made small-body exploration routine. Planetary defense and near-Earth object detection: A major segment explains how asteroid detection became a policy priority in the late 1990s and how congressional mandates gradually expanded from finding kilometer-scale objects to smaller, potentially regionally destructive ones. Deflection, mitigation, and emergency planning: The discussion covers practical strategies if a dangerous asteroid is found, including kinetic impactors, nuclear standoff deflection, gravity tractors, and government contingency planning through multi-agency exercises. Policy, governance, and international coordination: The hosts explore how asteroid response would require international cooperation, complicated by national priorities, potential weaponization of mitigation tools, and the UN/COPUOS framework. Asteroid mining and commercial space: The conversation shifts to private companies and legal questions surrounding asteroid resources, focusing on the Outer Space Treaty, U.S. commercial law, and the business logic behind mining water ice and precious metals. The future of asteroid missions and science priorities: They argue asteroid missions may be moving from Discovery into New Frontiers and possibly flagship territory as scientific questions deepen and low-hanging fruit is exhausted.

Key Arguments: Asteroids and comets are scientifically valuable as preserved remnants of solar system formation, making them prime targets for sample return and exploration. NASA’s early lack of asteroid missions was due to limited knowledge, bigger flagship priorities, and insufficient funding, not lack of interest in principle. Competitive small-mission programs like Discovery made asteroid and comet exploration feasible and disproportionately successful. Planetary defense only began to receive sustained attention in the late 1990s, and funding increased mainly when asteroid detection aligned with human spaceflight goals. Current detection capabilities are improving, but identifying smaller near-Earth objects still requires dedicated space-based assets to reach policy goals. Mitigation is technically possible in principle, but requires early warning, long lead times, tested hardware, and international political coordination. The legal basis for commercial asteroid mining remains ambiguous because the Outer Space Treaty bars national appropriation but U.S. law now explicitly supports commercial resource recovery by citizens. Private asteroid companies may initially make money through adjacent markets like remote sensing, hyperspectral imaging, and space situational awareness before actual mining becomes viable.

Data Points: OSIRIS-REx sample return: 60 grams to 2 kilograms - Estimated amount of asteroid material to be returned to Earth from Bennu. New Frontiers mission cost cap: ~$1 billion including launch vehicle - Budget class for OSIRIS-REx and similar medium missions. Discovery mission cost class: under half a billion dollars - Budget range for smaller competed planetary missions. Halley’s Comet return interval: about 75 years - Used to explain the 1986 close approach and NASA’s missed opportunity. 1980s planetary science launches: 2 launches - Galileo and Magellan were the only planetary science launches in the decade. Discovery missions to asteroids/comets: 5 of 10 launched missions - Out of roughly ten Discovery missions, five targeted asteroids or comets. Initial NEO search mandate: 90% of kilometer-or-larger asteroids by 2010 - 1998 congressional directive commonly referred to as Spaceguard-style survey goals. Early NEO search funding: $4 million per year - Approximate annual spending on asteroid detection before later increases. Later NEO search funding: $20 million per year - Funding rose after asteroid detection was tied to human spaceflight goals. Subsequent NEO budget: $40 million per year - Budget doubled again after the Chelyabinsk impact and the Asteroid Redirect Mission context. Current/near-current NEO budget mentioned: $50 million per year - Later reference to the detection program budget. Chelyabinsk impact injuries: ~1,100 people injured - People were hurt by broken glass after the blast wave from the atmospheric explosion. Discovery of larger NEOs: about 95% found - Approximate completion of the kilometer-class asteroid detection effort. Lower-size NEO detection progress: about 15% found - Rough progress on the much larger population of 140-meter-class asteroids. NEO survey target for regional threats: 90% of 140-meter-or-larger asteroids by 2020 - Congressional/NASA goal that was recognized as unattainable on the existing funding path. NeoCam expected yield: 60% in four years - A proposed space-based survey telescope could find roughly 60% of regionally threatening asteroids within four years.

Pivotal Quotes: "These are kind of these mid-size missions that can do a little bit more." — Casey Dreyer: Describing the New Frontiers mission class and why OSIRIS-REx matters. "The 1980s in planetary science are often referred to as the lost decade of planetary science." — Jason Callahan: Explaining the absence of missions and the advocacy roots of the Planetary Society. "If we're really serious about Astro Defense, which we are clearly not, because if we were, we would right now have on the shelf at some clean room somewhere a kinetic impactor spacecraft just ready to go." — Matt Kaplan: Critiquing the gap between planetary defense rhetoric and actual preparedness.

Implications: Asteroid science is moving from niche exploration to strategic infrastructure: early warning, deflection capability, and eventual resource extraction. But progress will depend on dedicated funding, international coordination, and clearer legal rules for private activity in space.