asteroidsquads/issb – a synergetic neo deflection campaign ... · iaa sg35finalreport.pdf neas Ø...

Folie 1AsteroidSQUADS > jtg RY-OR HB > PlanDefCon2011 > 11 MAY 2011 09:10

2011 IAA Planetary Defense Conference – From Threat to Action

ASTEROIDSQUADS/iSSB – a Synergetic NEO Deflection Campaign and

Mitigation Effects Test Mission Scenario

J.T. Grundmann@, S. Mottola, M. Drentschew*, M. Drobczyk, R. Findlay, M. Hallmann, A. Heidecker, R. Kahle, E. Kheiri, A. Koch, V. Maiwald, O. Mierheim, F. Nohka,

D. Quantius, M. Siemer, P. Zabel, T. van Zoest

DLR German Aerospace Center* ZFT Zentrum für Telematik

@ [email protected]


Origins in the rearview mirror…

1st IAA Planetary Defense Conference White Paper recommendations:

live test of asteroid deflection methodsstudy momentum transfer (particularly kinetic interceptor)

„Fund research and conduct flight experiments to characterize and refine the effectiveness of Kinetic Impact as a deflection technique.”

exercise and test existing space and civil defence infrastructure develop response protocols & international participation

„Future conferences should encourage the development of deflection campaigns […]. The campaign design should specify the campaign and mission timelines, launch vehicle(s) and spacecraft, deflection option(s), and resource requirements for such an effort.”

overall focus of 2009: sub- & small PHOs (20 m < Ø < 500 m)


…from the memorable quotes department...

„Almost all victims are caused by km-size NEOs but the Tunguska type we are most likely to see.“

„The risk of surprise by a large impact has been almost completely retired.“

„The risk of impact has not changed by doing asteroid surveys alone.“

„At a point in time you just will have to go out to one there and just hit it with something.“

„The one thing we must not be afraid of is to look stupid on camera.“


…and the devil in the details.*

images: l.: Gustave Doré, r.: Cervantes, ©1605,inset Dan Durda* lyrics: The Walkabouts

even dedicated scientific NEA missions are notoriously hard to sell

long interplanetary flight time to rendezvous with target

visually least attractive, most unspectacular targets

technology limits payload to object of interest

science yield tied to new technology

size down, risk up…

* …you are as brave as you believe - you are as brave as what you won't repeat … the future is a slow retreat - the future is a muscle you don't have…


AASTEROIDSTEROIDSQUADS/iSSBSQUADS/iSSB

…or how to solveone problem

by adding5 more :

images: special effects screenshots from Raumpatrouille Orion – Ep.2 – Planet außer Kurs, Sat.01.Oct.1966, Bavaria Filmstudios


notnotΘΘworkworkHeavy Launcher Development

testing is very expensivebillion dollar comsat passengers routinely taken for test flights~3 non-perfect flights in the first 10 typical before steady commercial-grade performance achievedresulting low cadence in first crucial marketing phase

Space Debris‚realistic‘ GTO/GEO launch vehicle tests litter space with big targets inviting local Kessler cascade big dead lead-sats placed close to most sensitive orbit (CoC-compliant or not…)

Planetary Science ‚big‘ science just too Cluster‘d to fly on new launch vehicles ‚small‘ NEO mission funding hard to get past the windmills

Planetary / Civil Defencedeflection campaigns: paper exercisesmulti-spacecraft operations: terra incognitaon-target performance: unknown

Concerned Politicsplanetary defence tests seen as the thin end of a very expensive & risky standing defence wedgeweaponization risk – the target of deflection may as well be on Earthtechnology dual use potential e.g. for covert missile defence testingperceived as preparatory to non-conventional high energy options

Cognitive Bias but km-class NEOs are the real killers, they said but not in my lifetime but Bruce Willis solved that, didn‘t he?but we don‘t have a chance


networkHeavy Launcher Development

proper ‚Heavy‘ testing with GTO or GEO-like burn profilemid-range payload stack mass from small net payload massslightly less than perfect performance may be tolerablelead-free real payload to prove launcher capabilities ‚all-up‘multiple-payload capabilities demonstration easily fitted in

Space Debrislow space debris generation risk trajectory possiblenon-standard orbits for all separated itemspayload stack most likely escapes or re-enters no CoC out there…

Planetary Sciencefast mission scenarioquite a bit of ‚pure‘ science potential beyond immediate deflection-related contextlow-cost set of instrumentsinstrument mix possiblebreak the one-mission-per-career-life routine

terms and conditions apply

Concerned Politicsindependently observable by amateur astronomers and professional science communityimpactor too small to include anything but ist own masscamera payload similar to interplanetary probessmall, low-cost, serialized production spacecraftcloser to commercial than ‚hardened‘ technologies

Cognitive Biasputs focus on most frequent NEO impact event class with a significant risk attacheddemonstrates concepts and capabilities in a practical and visible way

Planetary / Civil Defencedeflection campaigns: realistic global exercises!multi-spacecraft operations: practice possible!on-target performance: space spectacular!

background image: NASA


6 1 synthesis as a campaign & mission timeline

small & smart interceptor spacecraft and mission-specific launcher hardware produced well in time for first flight test of a new or upgraded heavy launcher

launcher test schedule triggers search for suitable target ( ~3..6 months to launch)complete flight time ≤ 3 months (launch to final damage assessment photo opportunity)target selection from networked operating surveys, with NEA catalogues as back-upwithin launch site trajectory constraints for GTO/GEO-like ascent profilestill in the night sky when hit, for ground-based observationswithin radar range before & after impacts (Goldstone at least)

shoot at what‘s delivered by nature (play the real thing - within above constraints)focus on deflection test and ground ops exercises, no science-driven target selectionelement of chance welcome! (orbit parameters, encounter Δv, target composition)

hot interceptor relays final death plunge telemetry to next inbound interceptor for store-forward transmission to Earth at lower rate, via high-gain antenna

video: up to 1000 frames/sec 1 frame per m per km/s encounter-Δv (~17 km/s avg.)on-board automatics tests possible (e.g. pre-set ‚special event timer‘ by telemetry ping)


vital statistics at a glance…

every month, ~8…20 known NEOs approach Earth to within 0.2 AU ≈ 78 Lunar Distances (LD)

listings are published by the MPC *

1.6 km1757.5 LDJun 12002 JC

2.5 km16.165.3 LDMay 52003 YT1

1.2 km17.975.5 LDMay 52008 FU6

23 m26.48.6 LDMay 22009 UK20

10 m28.28.9 LDApr 272008 UC202

2.2 km16.462.5 LDApr 152002 DB4

2.6 km16.145.5 LDMar 102000 PN9

1.8 km1767.7 LDFeb 202003 YG118

15 m27.39.3 LDJan 302011 BF10

62 m24.12.2 LDJan 262011 AL37

39 m25.48.3 LDJan 202011 BW10

18 m27.00.9 LDJan 202011 BY10

29 m25.99.5 LDJan 192011 AB37

9 m28.50.8 LDJan 172011 AN52

SizeMag.Miss DistanceDate(UT)Asteroid

extracts are carried by many sites, e.g. spaceweather.com, here as of 26 JAN 2011

a similar number of mostly small NEOs is discovered every month

mostly discovered a few days before closest approachmostly much closer to Earthmostly „Tunguska-sized“

PHO surveys getting into gear now * http://www.cfa.harvard.edu/iau/lists/CloseAppLong.html


…on the edge between dimple and bump

graphs: adapted excerpts of A.W. Harris (U.S.) via I. Bekey, IAA sg35finalreport.pdf

NEAs Ø > ~20 mcan cause massive low-altitude airbursts at the ≥1 Mt-TNT levelbegin to penetrate the shielding provided by the atmosphere

NEAs ~50 m < Ø < 1 kmcarry the second, regional component of lethal risk are in the focus of the new survey goals @ Ø > ~140 m

NEAs Ø < 700 mcover the range of the sub-power-law population‚bends‘ in the population curve may mark transitions between different regimes of NEA structure and/or composition

NEAs ~50 m < Ø < ~300 m

100 m / 100 Mt / 100 centuries class – 1 % likelihood per century

upper end of „Tunguskoids“ – lower end of PHO size definitions

covers crest of the ‚shallow bump‘ of lethal risk


instruments

Ranger-like camera bankcommercial photo & amateur astronomy optics adapted

short mission - low total radiation dose!

narrow, medium & wide-angle cameras (NAC, MAC, WAC)main drivers:

guidance at a wide range of distances throughout the mission, last-millisecond close-up surface photography, remote observation of impact ejecta coma

NAC: typical planetary 1K² conventional FT-CCD (or EMCCD for marginal optics), ~1.5° Field of View, ~10...17 fps, panchromatic, at least 2 cameras parallel

MAC: 512² or TV format (PAL / NTSC EMCCD available), ~5° FoV, ~50...72 fpsWAC: ultra-fast kpixel@kframes sensor (e.g. 128² AO EMCCD), ~15° FoV, ~1 kfps

common max. pixel clock of 18…20 MHz & moderate A/D resolution and/or look-up table compression of brightness from ≤ 12 bit A/Dif any, fixed strip filters for taxonomy, possibly also TV-style colourno filter wheels, but e.g. multiple WAC camera heads & rolling read-outstill ≥ 100 Mbps at full speed on each camera / sensor type, per channel



yet more instruments?

maybe dust countersemphasis on size-frequency counting likely due to unknown contamination of ejectadust composition analyzers only if thought feasible due to differential analysis

different types of impactors, e.g. bare vs SYLDA- or upper-stage-sheperding spacecraftembedded tracer compounds in impactors, e.g. non-toxic, non-radioactive exotic elements expected to be rare in target

maybe plasma instruments: the usual suspects…?volatiles: interstitial, impact-generated, impactor contamination, solar wind interactiondifferences in natural and artificial coma properties

definitely: more instruments displace cameras not required for guidance



ASTEROIDFINDER & other ‚Kompaktsatellit‘ baselines

BIRD TET (/SSB) (/SSB)22. Oct. 2001 launch this year secndary payload (‚piggy-back‘) launch dedicated launch620 · 620 · 550 mm³ 880 · 620 · 550 mm³ 1000 · 800 · 800 mm³ 2120 · 1000 · 800 mm³92 kg 120 kg 150 kg 138 kg

DLR-internal competition for first ‚Kompaktsatellit‘ science payload in 2008requirement of heritage re-use based on TET spacecraft & payload mass, power & volumerequirement for payload pushing technical limits

ASTEROIDFINDER:1st iteration: TET envelope + deployable sunshield + 45° solar panel

2nd iteration: TET-driven smallest common denominator ‚piggy-back‘ box3rd iteration: dedicated launch & eliminate deployable sunshield

propagation to other studies, e.g. Carbonsat-C, Carbonmon, AHAB,…

ASTEROIDSQUADS

135 kg


never a „Standard-…“ in the CEF –the ‚Kompaktsatellit‘ way of design

the out-of-the-drawer bus kit – a menu of options on unit level and subsystem leveloptions of dissimilar maturity can be combined in similar system due to well known interfacesstarting point in this study: the last state of the ‚piggy-back‘ „AsteroidFinder/SSB“ baselineevolution of a payload-requirements-driven bus solution in ~1 Concurrent Engineering weekfeasibility study in ~3 weeks with extensive Concurrent Engineering methods (& facility) use

the suffix »/SSB« originally »/StandardSatellitenBausatz« ≈ ≈ the »same-ol, same-ol kit« , not a »/StandardSatelliteBus«

BIRDTET

AsteroidFinderCHARM

flight-provenspace qualified

developedbreadboarded

designedstudied

LiveSat

structure

maturity

BIRDTET

AsteroidFinderCarbonMonmore CEFs…

C&DH BIRDTET

power

AsteroidFinder

BIRDTET

comms

AsteroidFinder

BIRDTET

wheels

BIRDTET

AsteroidFinder

battery

BIRDTET

gyros

AsteroidFinder

X antennaAsteroidFinder

BIRDcoarse sun s.

BIRDS antenna

BIRD

TET

GPS

PROBA-2 commercialcommercial

Phase BPhase APhase 0

CEF

[Payload]/BIRD[Payload]/TET[Payload]/SSB

[Payload]-C[ompact]subsystem reuse

naming the options: [Payload]/[Platform]

unit reusecomponent reuse

AsteroidFinder

CarbonSat-C


Ka-bandantenna

X-bandantenna

CFK Plate with MLI

Front EndElectronic

InterconnectionModule

Solar array

MLI Cover

High ResolutionCamera

Middle RangeCamera

Webcam

Propulsion

Bus

Cold Radiator

the kit


Interceptor Configuration

50 degreeSunshield

Propulsion (8 x 1N thrusters, 1x 400N thruster)

ACS

1 x Ka-band antenna 2 x X-band antenna 4 x Interlink antenna

Communication

2 x High Resolution Cameras4 x Middle Range Camera4 x Webcam

Payload

179kgMass

1m x 0,78m x 0,7mDimension

1m

0,78m

0,7m

+ a few negotiable protrusions

incl. 35 kg instruments& 25 kg propellant


0

200

400

600

800

1000

1200

0 2 4 6 8 10v, km/s

h, k

m

GTO AsteroidSQUADS

‚heavy‘ launcher performance model

dated but off-the-shelf available parametric study project performance model of a moderately upgraded Ariane 5 configuration

selected from a set of models by matching GTO performance with reasonable extrapolations of market requirements for the present decade

~12 t payload mass to GTO1..4 comsats delivered per launch to GTOGTO launch window ~22:20…23:20 UTC

upgraded cryogenic upper stage + mild tuning of core stage and booster

model combined with flown payload stack structures and fairingsshort fairingSYLDA dual launch structureSPELTRA triple / multiple launch structureASAP-5 auxiliary payloads carrier platform structure

ASAP – Ariane Structure for Auxiliary PayloadsSPELTRA – Structure Porteuse Externe pour Lancements Triple Ariane

(now: … pour Lancements Multiples)SYLDA – SYstème de Lancement Double Ariane


0

200

400

600

800

1000

1200

0 200 400 600 800 1000 1200t, s

h, k

m

GTO AsteroidSQUADS

‚heavy‘ launcher escape performance

payload mass off-loading to exceed escape velocity safelyapply GTO burn sequence as for maximum payload to GTOescape velocity design goal:

impact at ~0.05 AU from Earth – maximum PHO Emoidv∞ ~ 1 km/s – reasonably safe launcher performance margin

acceptable design range:~450 m/s < v∞ < ~3.8 km/s after 90 days:

out of Earth-Moon zone of influenceimpacts at < 0.2 AU – MPC long fly-by list limit

baseline performance of selected launcher model: 2 payload blocks can be delivered to interplanetary space

v∞,2 = 3060 m/shigh but still acceptable

3 payload blocks can not escape the Earth-Moon systemQ3 ≈ 130000 km

partial block off-loading unlikely to achieve minimum escape conditions


6,71

m

4m

4,57m

12,4

4m

1 interceptor with comsat cone (medium impactor)

8 interceptors on ASAP ring underfairing (baseline impactor)

1 interceptor attached to SYLDA shell under comsat cone (heavy impactor)

1 interceptor with comsat cone

8 interceptors on ASAP ring underSYLDA

1 interceptor attached to upper stageunder comsat cone

Launcher Configuration:20 impactors – 2 medium – 2 heavy




idea: do S-L 9 sub-PHO @ 10‘s of LD

ASTEROIDSQUADS/iSSB:Serendipitous Quantitative Understanding and

Assessment of Deflection Strategiesusing the DLR Kompaktsatellit bus kit evolved

and improved for interplanetary flight

not to scale

note: there ain‘t no such thing as a free launch. (payload not including space debris)

images: t.: NASA, b.: geosmile.de


flotilla impact sequences – close pair Ø 140 mΔv = 17 km/s

Δs = 26000 kmΔt = 25 min100 Mbps

s = 5500 kmΔt = 5.5 min

Δs = 250000 kmΔt = 4 h5 Mbps

Δs ~ 26000 kmΔt ~ 25 min

5 Mbps

Δs ~ 0.05 ≤ 0.2 AU~3 Mbps

NAC NAC NAC NAC NAC NACMAC

MAC

MAC

MAC

MAC

MAC

MAC

MACWW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WW

WWWW

NACNEA ≥ 1 pixel:s = 5500 kmT - 5.5 min1024² pixel

17 fps

NACNEA full frame:

s = 5.5 kmT - 0.32 s

1024² pixel17 fps

MACNEA full frame:

s = 1.6 kmT - 0.094 s512² pixel

48 fps

WACNEA full frame:

s = 0.5 kmT - 0.031 s128² pixel966 fps

WA

C: 30 fram

es to impact

NEA ≥ 1 pixel:s = 68 km

T - 4 sNEA ≥ 1 pixel:

s = 820 kmT - 48 s

Δt ≤ 90 d


flotilla impact sequences – single impactor Ø 140 mΔv = 17 km/s

s = 5500 kmΔt = 5.5 min

Δs = 250000 kmΔt = 4 h5 Mbps

Δs ~ 26000 kmΔt ~ 25 min

5 Mbps

Δs ~ 0.05 ≤ 0.2 AU~3 Mbps

NAC NACMAC

MAC

W

W

WW W

NACNEA ≥ 1 pixel:s = 5500 kmT - 5.5 min1024² pixel

< 1 fps

NACNEA full frame:

s = 5.5 kmT - 0.32 s

1024² pixel< 1 fps

MACNEA full frame:

s = 1.6 kmT - 0.094 s512² pixel~ 2.4 fps

WACNEA full frame:

s = 0.5 kmT - 0.031 s128² pixel~48 fps

WA

C: ~1±1 fram

es to impact

NEA ≥ 1 pixel:s = 68 km

T - 4 sNEA ≥ 1 pixel:

s = 820 kmT - 48 s

Δs ~ 26000 kmΔt ~ 25 min

5 Mbps


6,71

m

4m

4,57m

11,5

m15

,5m

outlook & future work:more serious launchers, more serious targets

Apophisto Earth

1999RQ36 to Earth

Toutatisto Earth

1950DA to Earth

AsteroidSQUADS to Toutatis

AsteroidSQUADS to 1999RQ36

AsteroidSQUADS to Apophis

AsteroidSQUADS to 1950DA

Launch Epoch (UTC)

Rel

ativ

e D

ista

nce

(km

)

Conjunctions between AsteroidSQUADS and Asteroids Depending on Launch Date (Transfer Time up to 500 Days)


Conclusions

the combination of a heavy launch vehicle test flight with a useful planetary defence methods test and infrastructure exercise is feasible

the effort to set up the space segment using multiple small spacecraft with largely identical configurations is estimated to be comparable to a medium-class mission, but a career lifetime of science work is not at risk

re-flight in case of launcher failure is technically not difficult due to the series production infrastructure previously set up for the first attempt

a high risk of failures and performance below the envisaged level is not just accepted, but taken as a chance to learn in time and with time

the expenses can be shared by all parties participating in the campaign by paying for their own activities conducted under the common scenario


Questions?

Who knows whether, when a comet shall approach this globe to

destroy it, as it often has been and will be destroyed, men will

not tear rocks from their foundations by means of steam,

and hurl mountains, as the giants are said to have done,

against the flaming mass? - And then we shall have traditions of Titans again, and of wars with

Heaven.

Lord Byron, 1822

images: l.: via wikipedia 2008, r.: geosmile.de


back-up slides

bus accommodation detailssolo impactor mass budget40 impactor stack details500 day encounters enlargedorbit plot Earth & Moon – ASTEROIDSQUADS – Apophis


1N Thruster

400N Thruster

Propellant Tank (6l)

HeliumTank (0,7l)

Sun sensor

X-bandTrans/Rec

X-bandTransponder

PayloadDPU

Battery

PowerBoards

C&DH

Ka-bandTrans/Rec

InterlinkTrans Gyro

Interlink antenna


Mass Budget

1,5 kgLauncher I/F

179 kgOverall

20 kgHarness

9 kgThermal

1 kgACS

17 kgPower

10 kgC&DH + DPU

35 kgPayload

17,5 kgCommunication

25 kgPropellant

26 kgPropulsion

17 kgStructure

Communication10%

Structure9%

ACS1%

Propulsion15%

Propellant14%

Thermal5%

Payload19%

C&DH + DPU 6%

Power9%

Launcher1% Harness

11%


6,71

m

4m

4,57m

11,5

m15

,5m 1 interceptor with comsat cone

8 interceptors on ASAP ring underfairing

1 interceptor attached to SYLDA shellunder comsat cone

1 interceptor with comsat cone

8 interceptors on ASAP ring underSYLDA

1 interceptor attached to SPELTRA shell or upper stage under comsat cone

outlook:upgraded launcher configuration with ASAP




Rel

ativ

e D

ista

nce

(km

)Conjunctions between AsteroidSQUADS follow-on and Asteroids Depending on Launch Date ( Transfer Time up to 500 d )

1950DA to Earth

Apophisto Earth

1999RQ36 to Earth

Toutatisto Earth

AsteroidSQUADS to Toutatis

AsteroidSQUADS to 1999RQ36

AsteroidSQUADS to Apophis

AsteroidSQUADS to 1950DA

Launch Epoch (UTC)

Assumptions: Ariane 5 study model, GTO launch window ~22:20-23:20 UTC, inertial velocity after launch: 10.7703 km/s v_infinity: 3.06 km/s; 20 impactor stack; no mid course manoeuvre; Transfer duration up to 500 days allowed approaches of ~ 1 Gm (0.0067 AU) relative distance reached

asteroidsquads/issb – a synergetic neo deflection campaign ... · iaa sg35finalreport.pdf neas Ø...

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