Ian Carnelli – ESA-ESTECESA’s Don Quijote mission September 2006 NEO deflection mission studies: DON QUIJOTE MISSION Ian Carnelli ESA’s Advanced Concepts

Ian Carnelli – ESA-ESTECESA’s Don Quijote mission September 2006

NEO deflection mission studies:

DON QUIJOTE MISSION

Ian Carnelli

ESA’s Advanced Concepts Team ESA ESTEC


NEO Mission Preparation at ESA

Motivation– Low impact probability but extremely severe effects – Very limited practical knowledge of the NEO threat and the best

technology approach to tackle it– Council of Europe

UN COPUOS OECDUK government task force

ESA to take action and identify the potential role of space missions


2000 – 2003 Early ESA scientific and system studies, 6 parallel mission feasibility studies (GSP):

July 2004 ESA's NEOMAP recommendations issued:priority prove our ability to modify the trajectory of a NEOfocus on the "Don Quijote" mission concept

Dec 2004 - Jun 2005 ESA's internal assessments at ESA/ESTEC's Concurrent Design Facility with JAXA participation.

March 2006 industrial phase-A mission studies kicked off.

ESA NEO mission definition activities

Simone

Earthguard 1

Nero

Don QuijoteIsh

tarEuneos


Industrial teams

Alcatel Alenia Space+ QinetiQ (EP subsystem)+ NGC aerospace (Impactor terminal navigation)+ SCI consultants: IFSI, OATo, OdP, UdR, UoM, OCA

EADS Astrium GmbH+ Deimos (Mission analysis, RSE and Ops)+ EADS Casa (thermal subsystem)+ SCI consultants: UniPi, DLR, Spaceguard Foundation, …

QinetiQ+ Swedish Space Corporation (Orbiter design)+ Verhaert Space (Impactor design)+ SCI consultants: SciSys, Open University


Objectives of the studies

Review the results of the ESA/CDF NEO2 study Critically review mission requirements Assess different design concepts and feasibility Provide mission architecture & design of all elements Use cost-effective approach Identify development risks and critical technologies Perform a cost analysis Provide programmatic


KO PM1 PM2 PM3 PM4MTR FP

Study planning

NOW


Programmatic Design Drivers

“Cost-aware” approach1. Re-use of existing components with TRL ≥ 6

2. Modular design + commonalities between Orbiter & Impactor

3. Emphasis on autonomous operations

4. Small class launchers baselined (Dnepr, Vega)Medium-class launchers (Soyuz) considered only when performances of small launchers deemed insufficient and if operational advantages exist.


Mission objectives

“DQ light” – primary objectives:1. Impact a give NEO2. determine momentum transfer

(Mass, size, density, CoM orbital parameters …)

“DQ+” – secondary objectives:all primary objectives+ multi-spectral mapping+ ASP-DeX+ (optional) thermal & mechanical properties


Main mission requirements

System operations

2 s/c launched separately

Impactor launched after Obiter successful rendezvous

min. 2 months RSE campaigns before and after impact

ASP-DeX to be carried out only at end-of-mission

Impactor

NEA CoG Δa ≥ 100 m

K = 1 (no ejecta)

Target visual acquisition 2 days before impact

Autonomous optical navigation 2 days before impact

Impact accuracy 50 m (3σ) from CoG


Main mission requirements

Orbiter

Δa measurement accuracy 10 m

Measure at least NEA mass, size, gravity field, shape

Back-up data relay for Impactor’s GNC

Observe impact from safe parking position

30 days autonomy during interplanetary cruise

Autonomous navigation while orbiting ≥ 4 orbits

Autonomous optical rendezvous when distance ≤ 100 km

TechnologyTRL ≥ 5 by mid-2008 for Orbiter autonomy & Impactor GNC

TRL ≥ 6 by mid-2007 for all other system elements


Mission scenario

Flexibility:1. Operational & programmatic: 2 separate missions for Orbiter

and Impactor(possible different primes, evenly distributed funding effort)

2. Design: 2 different targets allow to have a robust design that can adapt to new scenarios (alternative targets) and large uncertainties in asteroid properties (phase-A only).


Target selection (NEOMAP)

Orbit characteristics Preferred range

Rendezvous ΔV < 7 km/s

Orbit type and MOID Amor and increasing MOID

Orbit determination accuracy Well determined orbits

Physical characteristics Preferred range

Size < 800 m diameter

Density 1.3 gm/cm3

Absolute magnitude H 20.4 - 19.6

Shape Not irregularly shaped

Taxonomic type C-Type

Rotation period 6 – 20 h

Binarity Not binary

2002AT4

1989ML


Target selection

2002AT4 1989ML

Size and Mass

SmallerLess massive

LargerMore massive

OrbitLarger semi-major axisHigh eccentricity

Smaller semi-major axisSmall eccentricity (within Mars orbit)

Implications for Orbiter

High ΔV to reach targetComplex and lengthy transfer

Smaller ΔV to reach targetEasier and shorter transfer

Implications for Impacter

Harder to detect and targetEasier to deflect

Easier to detect and targetHarder to deflect

Sizing case for Orbiter Sizing case for Impactor


System design

Commonalities between Orbiter and Impactor design identified on system, sub-system and component level

Different approaches in GNC and EP subsystem design Alternative solutions:

Common Propulsion Module Impactor-PM integrated approach Common Orbiter-Impactor bus


Strawman payload

Deflection measurement (mandatory):– Optical camera– Radio Science

Ancillary data (high priority)– Laser/Radar altimeter to speed dynamic model convergence and/or

enhance measurement accuracy– Thermal IR spectrometer (Yarkowsky effect)

Scientific studies (+ NEO mitigation characterization)– NIR spectrometer for mineralogy, X-ray spectrometer– Dust analyzer/detector to interpret impact objective– Second camera– Magnetometer, Radiation monitor, in-situ characterization (ASP)


Developing capabilities

Autonomy Orbiter:

– 30 day autonomy during interplanetary cruise– autonomous optical rendezvous < 100 km distance– close proximity operations (drift-bys, safe parking, orbit)– orbit around a small body for RSE

Impactor:– Impactor autonomous navigation 2 days before impact– Impactor final targeting architecture


Summary

Don Quijote is a deflection precursor mission

reduce technology risk if the approach was used on a real threat

Information obtained could be useful even in other type of deflection techniques (i.e. non-kinetic impact was)

In a particular case (resonant returns of small asteroids e.g. Apophis) DQ could:

1. remove any uncertainties on the orbit of the object and its orbital evolution (including Yarkowsky)

2. deflect the asteroid out of a keyhole

In-orbit technology demonstration: focus on-board autonomy for interplanetary spacecraft

Flight proven technology, except for vision-based Autonomous GNC

Historic mission - opportunity to enhance public support in space


Documents

Ian Carnelli – ESA-ESTECESA’s Don Quijote mission September 2006 NEO deflection mission studies: DON QUIJOTE MISSION Ian Carnelli ESA’s Advanced Concepts