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The Near-Earth Space Surveillance (NESS) Mission:
Discovering Near-Earth Objects with a Microsatellite
The Near-Earth Space Surveillance (NESS) Mission:
Discovering Near-Earth Objects with a Microsatellite
Seminar Presented at theSeminar Presented at theUniversity of Rochester onUniversity of Rochester on
24 Nov 200824 Nov 2008by Ed Tedescoby Ed Tedesco
11
22
Spacecraft is named Spacecraft is named “NEOSSat”“NEOSSat”
((Near-Earth Object Surveillance Near-Earth Object Surveillance Satellite)Satellite)
Spacecraft is named Spacecraft is named “NEOSSat”“NEOSSat”
((Near-Earth Object Surveillance Near-Earth Object Surveillance Satellite)Satellite)
Microsatellite is funded by:Microsatellite is funded by:- Defence Research & Development Canada - Defence Research & Development Canada
(Department of National Defence)(Department of National Defence)
- Canadian Space Agency (Industry Canada)- Canadian Space Agency (Industry Canada)
- Canadian Science Team support from Space - Canadian Science Team support from Space Sciences Sector (CSA)Sciences Sector (CSA)
- Prime contractor is Dynacon Inc.- Prime contractor is Dynacon Inc.
- Currently in Phase C - Currently in Phase C
- Launch early in 2010- Launch early in 2010
33
NEOSSat is a Dual-Use NEOSSat is a Dual-Use Mission...Mission...
NEOSSat is a Dual-Use NEOSSat is a Dual-Use Mission...Mission...
Asteroid Search:Asteroid Search:
NESS ProjectNESS Project
Some Near-Earth Asteroid Some Near-Earth Asteroid classes are difficult to observe classes are difficult to observe from the groundfrom the ground
Some are potentially Some are potentially hazardoushazardous
Some are potential future Some are potential future exploration targetsexploration targets
Searching and tracking from Searching and tracking from orbit offers advantagesorbit offers advantages
Satellite Satellite Tracking:Tracking:
HEOSS ProjectHEOSS Project
DND pursuing Surveillance DND pursuing Surveillance of Space (SoS) missionof Space (SoS) mission
Deeper understanding Deeper understanding needed in many areasneeded in many areas
DR&DC providing R&D DR&DC providing R&D supportsupport
A microsat is a fast, cheap A microsat is a fast, cheap way to test-fly SoS-way to test-fly SoS-relevant technologiesrelevant technologies
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NEOSSat Science TeamsNEOSSat Science TeamsNEOSSat Science TeamsNEOSSat Science TeamsAsteroid Science:Asteroid Science:(NESS Project)(NESS Project)Alan Hildebrand, U. Calgary (PI) Alan Hildebrand, U. Calgary (PI) Ed Tedesco, PSI (US Sci. Team PI)Ed Tedesco, PSI (US Sci. Team PI)Rob Cardinal, U. CalgaryRob Cardinal, U. CalgaryJaymie Matthews, UBCJaymie Matthews, UBCBrett Gladman, UBCBrett Gladman, UBCBrad Wallace, DR&DC Brad Wallace, DR&DC Peter Brown, UWOPeter Brown, UWOPaul Wiegert, UWOPaul Wiegert, UWOPaul Chodas, JPLPaul Chodas, JPLMikael Granvik, U. HelsinkiMikael Granvik, U. HelsinkiSteve Larson, U. Arizona Steve Larson, U. Arizona Simon P. Worden, ARCSimon P. Worden, ARCKieran Carroll, GEDEXKieran Carroll, GEDEXPete Gural, SAICPete Gural, SAIC
Satellite Tracking:Satellite Tracking:(HEOSS Project)(HEOSS Project)Brad Wallace, DRDC (PI) Brad Wallace, DRDC (PI) Frank Pinkney, DRDCFrank Pinkney, DRDCDoug Burrell, RMCDoug Burrell, RMCLauchie Scott, DRDCLauchie Scott, DRDCDon Bedard, DRDCDon Bedard, DRDCJim Rody, DRDCJim Rody, DRDCAaron Spaans, DRDCAaron Spaans, DRDCMartin Levesque, DRDCMartin Levesque, DRDCSylvie Buteau, DRDCSylvie Buteau, DRDCTom Racey, RMCTom Racey, RMCAlan Hildebrand, U.CalgaryAlan Hildebrand, U.Calgary
55
Why NEOSSat and Small Why NEOSSat and Small Bodies? Bodies?
Why NEOSSat and Small Why NEOSSat and Small Bodies? Bodies?
Science GoalsScience Goals
NRC (1998) “The Exploration of NEO’s”
•“To understand the orbital distribution, physical characteristics, composition, origin, and history of near-Earth objects.”
• The interaction of the NEO population with the planets
Societal GoalsSocietal Goals
• Understand Impact Hazard
• Identify Extraterrestrial Resources
66
MOST MOST (Microvariability and Oscillations of (Microvariability and Oscillations of
Stars)Stars)
MOST MOST (Microvariability and Oscillations of (Microvariability and Oscillations of
Stars)Stars)
Dynacon is Prime ContractorDynacon is Prime Contractor
Jaymie Matthews, PIJaymie Matthews, PI
Launched by Eurockot, June Launched by Eurockot, June 30, 200330, 2003
Stellar astronomy missionStellar astronomy mission
0.007 degree attitude control0.007 degree attitude control
Partner Universities:Partner Universities:
Univ. TorontoUniv. Toronto
Univ. British ColumbiaUniv. British Columbia
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NEOSSatNEOSSatNEOSSatNEOSSat
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Constraining the Atira (a.k.a. IEO) Constraining the Atira (a.k.a. IEO) Orbital Class Asteroid PopulationOrbital Class Asteroid Population
Constraining the Atira (a.k.a. IEO) Constraining the Atira (a.k.a. IEO) Orbital Class Asteroid PopulationOrbital Class Asteroid Population
99
The Inner Solar SystemThe Inner Solar SystemThe Inner Solar SystemThe Inner Solar System
1010
The Inner most Solar SystemThe Inner most Solar SystemThe Inner most Solar SystemThe Inner most Solar System
1111
NEO Orbital ClassesNEO Orbital ClassesNEO Orbital ClassesNEO Orbital Classes
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We live in a historic timeWe live in a historic timeWe live in a historic timeWe live in a historic time
1313
The U.S. Congress’ GoalThe U.S. Congress’ GoalThe U.S. Congress’ GoalThe U.S. Congress’ Goal
1414
Rationale for U.S. Congressional Rationale for U.S. Congressional GoalGoal
Rationale for U.S. Congressional Rationale for U.S. Congressional GoalGoal
1515
NESS ObjectivesNESS Objectives
- Search for new Near-Earth Asteroids (NEAs), focusing on Atens and Atiras
- Do follow-up tracking of NEA’s
- Assess potentially hazardous asteroids (PHA’s)
- Monitor cometary behaviour
- Enable radar imaging
1616
NEOSSat Advantages for NEA Searching
NEOSSat Advantages for NEA Searching
Can look close to the Sun:Can look close to the Sun:- Can discover IEOs, constrain population characteristics- Can discover IEOs, constrain population characteristics- Accelerate discovery rate for Atens, Apollos- Accelerate discovery rate for Atens, Apollos- Create opportunities for future NEA exploration missions- Create opportunities for future NEA exploration missions- Create radar-imaging opportunities in daylight sky- Create radar-imaging opportunities in daylight sky- Interrogate “impact keyholes” in daylight sky- Interrogate “impact keyholes” in daylight sky- Observe cometary behaviour close to the Sun- Observe cometary behaviour close to the Sun
Parallax: - Baseline of orbit diameter- Allows immediate distinction of NEAs from main-belt objects
24/7 availability = higher productivity
1717
Cataloguing Search Cataloguing Search EfficienciesEfficiencies
Cataloguing Search Cataloguing Search EfficienciesEfficiencies
1818
Warning EfficienciesWarning Efficiencies Warning EfficienciesWarning Efficiencies
1919
Spaced-based Sensor WinsSpaced-based Sensor Wins
- 0.5 LEO telescope out performs 4.0 m ground-- 0.5 LEO telescope out performs 4.0 m ground-based telescope in both cataloguing and warningbased telescope in both cataloguing and warning
- LEO deployment is superior to other space-based sittings for warning capability
2020
The First WarningThe First Warning The First WarningThe First WarningAsteroid 2008 TC3 was discovered on 06 October 2008 as part of the NASA-funded Catalina Sky Survey for Near-Earth Objects and impacted the Earth on 07 October 2008. An asteroid the size of 2008 TC3 (~3 m in diameter) impacts the Earth every few months, but this is the first time one has been discovered before impact.
2121
The First WarningThe First Warning The First WarningThe First WarningThe brief flash created when 2008 TC3 entered the atmosphere was captured by Meteosat-8 in Rapid Scan Service, as shown in the image below. (IR3.9 channel, 07 October 2008 at 02:45:47 UTC).
2222
The First WarningThe First Warning The First WarningThe First WarningThe aftermath of the entry of 2008 TC3 into the atmosphere over northern Sudan was also captured in a video frame (below), showing the remnants of the long-lasting persistent, twisted, high altitude trail.
Credit:
Mohamed E. A. Mahir (Noub NGO), Dr. Muawia H. Shaddad (Univ. Khartoum), Dr. Peter Jenniskens (SETI Institute/NASA Ames).
2323
NESS NEO Search RegionsNESS NEO Search Regions
+/-45 deg
+/-55 deg
+/-40 deg
“Ecliptic East” Region“Ecliptic West” Region
Search each patch 4 times each, once per month
Search patches each 0.86x 0.86 deg
2424
Richness of NEO Fields near the Sun optimizes search performance
(Boattini and Carusi, 1998)
Richness of NEO Fields near the Sun optimizes search performance
(Boattini and Carusi, 1998)
2525
Asteroid sky distribution to 300 m
(Harris et al., 2006)
Asteroid sky distribution to 300 m
(Harris et al., 2006)
2626
Simulated Atira Sky Densities (Masi, 2003)
Simulated Atira Sky Densities (Masi, 2003)
2727
Search Parameters can be Optimized for NEO Orbital Class
Search Parameters can be Optimized for NEO Orbital Class
40 50 60 700.00
0.02
0.04
0.06
0.08
0.10
0.12
Solar Elongation (deg)
IEOAtenECAMBA
2828
Simulated Search Performance: Atens and Atiras D > 500 m
Simulated Search Performance: Atens and Atiras D > 500 m
0 1 2 3
0
20
40
60
80
IEO 19
Aten 20
D > 500m 45° to 70° solar elongation; ±20° ecliptic latitude scanned monthly
IEO 20
Aten 19
Time (Years)
Co
mp
lete
nes
s (%
)
Aten 21
IEO 21
2929
Discovery Sensitivity to Asteroid Limiting Magnitude
Discovery Sensitivity to Asteroid Limiting Magnitude
14 15 16 17 18 19 20 21
0
10
20
30
40
V mag at Discovery
AtensIEOs
% p
er
0.5
mag
bin
D > 500 m
3030
Discovery Magnitude Distribution for Survey to V = 21
(56% of discoveries have V between 20 and 21.)
Discovery Magnitude Distribution for Survey to V = 21
(56% of discoveries have V between 20 and 21.)
3131
Phase Effects vs. Distance at Low Solar Elongations
Phase Effects vs. Distance at Low Solar Elongations
3232
Discriminating NEA asteroids of interest: Proper motions at discovery?
Discriminating NEA asteroids of interest: Proper motions at discovery?
-100 0 100 200 300
Ecliptic Longitude Rate (arcsec/hr)
0
20
40
60
80IEOAtenECA
N
3333
Proper Motions of Main Belt Asteroids at Discovery
Proper Motions of Main Belt Asteroids at Discovery
-100 0 100 200 300
Ecliptic Longitude Rate (arcsec/hr)
3434
Saved by Parallax – A Consequence of Orbiting Sensor
Saved by Parallax – A Consequence of Orbiting Sensor
0.0 0.5 1.0 1.5
Distance at Discovery (AU)
0
2
4
6D > 500 m and V 20 at discovery
IEOs
Atens
% D
isco
vere
d
3535
NEOSSat “Boldly Going”NEOSSat “Boldly Going”NEOSSat “Boldly Going”NEOSSat “Boldly Going”
- Will constrain Atira (IEO) population- Will constrain Atira (IEO) population
- Will explore the synergies between ground-based & space-based sensors- Will develop asteroid search software for a “parallatic” space-based sensor- NEOSSat will put Canada at No. 2 in the world at contributing to reduction of the NEO impact hazard in dollars invested