Synergistic Approach of Asteroid Exploitation and Planetary Protection

1. 2011 IAA Planetary Defense Conference Synergistic Approach of Asteroid Exploitation and Planetary Protection From Threat to Action Joan-Pau Sanchez

2. Introduction Possible synergies between space systems capable of deflecting realistic impact threat and, at the same time, gravitationally capturing small asteroids for later resource exploitation. • Low-thrust tugboatmodel as a space system. • Tugboat system attaches to theasteroid surface and provides continuous thrust. • Assessment on the capability of such a system to deflect realisticimpact threats. • Statistical population that could bemanoeuvre into Earth-bound orbits. Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture Source: ESA Joan Pau Sanchez

3. Deflection: Procedure Rendezvous Trajectory • 5,000 kg wet mass • v∞ of 2.5 km/s • Medium-to-large mission 1. Baseline Design Deflection Action Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture Earth orbit NEO orbit • 17,518 impactors. • The objective is to compute the mass of the largest object that the tugboat system could deflect from each one of the impacting orbits. Joan Pau Sanchez

4. Deflection: Set of Virtual Impactors • Complete set of weighted impactors: <p>=1% Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture <p>=0.2% <p>=0.05% <p>=0.01% <p>≤ 0.005% Set of virtual impactors plotted as dots of size and colour as a function of the relative frequency that should be expected for each impactor. Joan Pau Sanchez

5. Deflection: Planetary Protection Table 1: Impact hazard categories Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture Table 2: Levels of Planetary Protection Joan Pau Sanchez

6. Asteroid Capture Concept On the possibility of moving small near Earth asteroids and inserting them onto Earth bound trajectories for later utilization. • How much material could a 5000kg low thrust spacecraft transport back to Earth? Low Thrust is a very limiting constraint. • The final Earth orbit insertion needs to be ballistic or unaided by the propulsion system. Ballistic capture may be possible for objects with relative velocities v∞ below 1 km/s. Grazing aero-assisted trajectories may be possible to capture objects with relative velocities v∞ above 1 km/s. • Only aero-braking trajectories are designed so that maximum dynamical pressure does not exceed material Strength. Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture Joan Pau Sanchez

7. Asteroid Capture Concept • How much material could a 5000 kg low thrust spacecraft transport back to Earth? Table 3: Largest mass returned to Earth - parenthesis: fraction returned mass compared with the initial wet mass of the spacecraft Introduction Deflection: 1. Procedure 2. Impactors 3. Protection Asteroid Capture Joan Pau Sanchez

8. Thank you! Contact email: jpau.sanchez@strath.ac.uk