Date post: | 12-Jan-2015 |
Category: |
Documents |
Upload: | american-astronautical-society |
View: | 761 times |
Download: | 0 times |
Planetary Defense & NEO Exploration
49th GoddardMemorial Symposium
Thomas D. Jones, PhD
Greenbelt, MD
March 31, 2011
Hayabusa Return
Planetary Defense & NEO Exploration
2
Report
of the
NASA Advisory Council
Ad Hoc Task Force on Planetary Defense
October 6, 2010
http://www.nasa.gov/pdf/490945main_10-10_TFPD.pdf
Planetary Defense & NEO Exploration
Richard P. Binzel
Professor of Planetary Science
Massachusetts Institute of Technology
Clark R. Chapman
Senior Scientist
Southwest Research Institute
Lindley N. Johnson
Program Executive
Near-Earth Object Observations Program
HQ NASA
Thomas D. Jones
Visiting Senior Research Scientist
Institute for Human and Machine Cognition
(Task Force Co-Chair)
NAC Task Force on Planetary Defense
Russell L. Schweickart
Chairman, B612 Foundation
(Task Force Co-Chair)
Brian Wilcox
Principal Member of Technical Staff
Jet Propulsion Laboratory
Donald K. Yeomans
Manager, Near-Earth Object Program Office
Jet Propulsion Laboratory
Executive Secretary
Bette Siegel
Exploration Systems Mission Directorate
HQ NASA
Planetary Defense & NEO Exploration
• Search programs are rapidly increasing NEO discovery rate
• Many PHOs will have “worrisome probability of impact”• Threshold for concern? Impact probability of
1/1000? 1/100? 1/50?
• Imperfect information at time deflection decision needed
• Deflection decision frequency considerably higher than actual impact frequency (20:1, 50:1, 100:1?)
• International leadership needed: Inevitable risk shifting as impact point point is moved to eliminate risk for all
4
Planetary Defense & NEO Exploration
• NASA NEO activity is “3-D”: exploration, science,
planetary defense (PD)
• Minor incremental cost to “other” space missions
can yield large increase in PD knowledge
• Example: Science mission can demonstrate prox-
ops algorithms for PD, human exploration
• Example: NEO’s interior structure, physical
properties, and stability of surface materials
(for human exploration) aids PD planning
5
Synergies from Planetary Defense(1 of 2)
Planetary Defense & NEO Exploration
• Time is a 4th dimension of NASA’s NEO research• Early integration of PD results in faster maturity of
technology
• Eliminates cost of duplicate flight missions
• Integrating PD into science and human exploration
missions increases overall knowledge return• Meets needs of managers, policy makers, scientists, public
6Version 12
Synergies from Planetary Defense(2 of 2)
Planetary Defense & NEO Exploration
1. Organize for Effective Action on Planetary Defense
2. Acquire Essential Search, Track, and Warning Capabilities
3. Investigate the Nature of the Impact Threat
4. Prepare to Respond to Impact Threats
5. Lead U.S. Planetary Defense Efforts in National and International Forums
Task Force Recommendations
Planetary Defense & NEO Exploration
2.3 Short-term Warning:
NASA should investigate development of low cost, short-term impact warning systems
-- stats on small bodies, science cueing, public outreach
8http://fallingstar.com/danger.html
Planetary Defense & NEO Exploration
Space-based NEO Search:
Showing orbit geometry when Earth and the spacecraft are on approximately opposite sides of the sun. Earth-based telescopes will detect some NEOs that the space-based telescope will miss during the NEO perihelion passage. The resulting completeness will be better than with any single telescope.
Ball Aerospace
0 1 2 3 4 5 6 7 8 9 100.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Completeness for entire NEO population: IR space telescope only
All NEOs >140 m
All NEOs >60 m
Time (years)
Fra
ctio
nal
com
ple
ten
ess
90% completeness at 8.4 years
10
Planetary Defense & NEO Exploration
Amor
12
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Completeness on Human Exploration targets: IR space telescope only
>30 m
>60 m
Time (Earth years)
Fra
ctio
nal
com
ple
ten
ess
Planetary Defense & NEO Exploration
NEO Search ExplorationRisk Reduction
• NEO Search Will Fill in Operations “Flight Data File” • EVA, tools, science, rendezvous, descent, etc.
• Reduces Operations, Crew, and Program Risk• Known environment• Can prepare operations skill set• Verify mission is within crew capabilities• More targets reduced flight duration, mission ΔV
• Expanded program flexibility• Ties human exploration directly to human survival
Planetary Defense & NEO Exploration
Association of
Space Explorers
http://www.space-explorers.org
Art by Dan Durda