THEMIS MCRR GSFC 2/4/2004 THEMIS Mission Confirmation Readiness Feb 4 2004.

THEMIS MCRR GSFC 2/4/2004

THEMIS Mission Confirmation Readiness

Feb 4 2004


AGENDA

8:30 Introduction

F. Snow, GSFC

8:40 Science Overview

V. Angelopolous,UCB

9:00 Mission Overview

P. Harvey, UCB

9:40 Probe & Probe Carrier

M. Cully, Swales

10:00 SMO Assessment

M. Goans, SRO

10:30 RAO Cost Estimate

C. Fryer, SMO

11:00 Discussion

GPMC


THEMIS Science Overview

Dr. Vassilis Angelopolous

Principal Investigator

Space Sciences Laboratory

University of California, Berkeley


TIME HISTORY OF EVENTS AND MACROSCALE

INTERACTIONS DURING SUBSTORMS (THEMIS)

RESOLVING THE PHYSICS OF ONSET AND EVOLUTION OF SUBSTORMS

Principal InvestigatorVassilis Angelopoulos, UCB

EPO LeadNahide Craig, UCB

Program ManagerPeter Harvey, UCB

Industrial PartnerSWALES Aerospace

SCIENCE GOALS:Primary:

“How do substorms operate?”– One of the oldest and most important

questions in Geophysics– A turning point in our understanding

of the dynamic magnetosphere

First bonus science:

“What accelerates storm-time ‘killer’ electrons?”– A significant contribution to space weather science

Second bonus science:

“What controls efficiency of solar wind – magnetosphere coupling?”– Provides global context of

Solar Wind – Magnetosphere interaction


THEMIS determines where and how substorms are triggered.

Science Overview

• SEC Roadmap: “Understand energy, mass and flux transport in Geospace”

• SEC Roadmap: “How does solar variability affect society?”

• NRC, National Academy: A strategic question in space physics (1995).

Substorms are… …important to NASA:

AuroraCurrent disruption

Reconnection

• Auroral eruptions are recurrent (~3-6hrs) • Magnetospheric substorms are responsible for auroral eruptions.

• Fundamental mode of magnetospheric circulation

• Important for geo-storms have societal implications.

• Rich in new types of basic space plasma physics.


Events Occuring During a Substorm

CurrentDisruption

AuroralEruption

Reconnection

Current Disruption Model

time Event

0 sec Current Disruption

30 sec Auroral Eruption

60 sec Reconnection

Reconnection Model

time Event

0 sec Reconnection

90 sec Current Disruption

120 sec Auroral Eruption

?


Mission Elements

Probe conjunctions along Sun-Earth line recur once per 4 days over North America.

Ground based observatories completely cover North American sector; can

determine auroral breakup within 1-5s …

… while THEMIS’s space-based probes determine onset of Current Disruption and

Reconnection each within <10s.

: Ground Based Observatory


Science Objectives

THEMIS HAS FOCUSED MINIMUM (TO BASELINE) OBJECTIVES:

• Time History of Events…– Auroral breakup (on the ground)– Current Disruption [CD] (2 probes at ~10RE) – Reconnection [Rx] (2 probes at ~20-30RE)

… and Macroscale Interactions during >5 (>10) Substorms (Primary):– Current Disruption and Reconnection coupling

• Outward motion (1600km/s) of rarefaction wave • Inward motion of flows (1000km/s) and Poynting flux.

– Ionospheric coupling• Cross-tail current reduction (P5u/P4) vs flows• Field aligned current generation by flow vorticity, pressure gradients (P/dz, P/dx).

– Cross-scale coupling to local modes• Field line resonances (10RE, 5 min)

• Ballooning modes, KH waves (1RE, 1min)

• Weibel instability, cross-field current instability, kinetic Alfven waves (0.1RE, 6Hz)

• Production of storm time MeV electrons (Secondary)• Control of solar wind-magnetosphere coupling by the bow-shock,

magnetosheath and magnetopause (Tertiary)


Probe conjunctions well understood

BASELINE: >10 substorms achieved w/ 5 probes in 2 yrs & 50% margin.

MINIMUM: >5 substorms achieved in 1yr w/ 4 probes.

– computations include lunar, solar, drag, J2 terms

– YP1/2/3/4/5<±2RE; ZP3,4,5/NS<±2RE; ZP1,2/NS<±5RE

• Ascent design is optimal for science

– maximizes conjunctions, minimizes shadows

• … immune to launch insertion errors

– small, piece-wise Vs increase placement fidelity

• … and immune to probe insertion errors.

– Can withstand insertion error of V=80cm/s on any probe

Actual conjunction times in 1st year

Target orbit P1 P2 P3 P4 P4Period (days) 4 2

Apogee (RE) 30 19 12 12 12

Perigee (RE) 1.5 1.2

Inc @ midtail

Drift @ apg., @6:30UT

Knowledge @ apg.

Y<1RE/month

100 km

1

1.16

<7o <9o


Mission overview: Fault-tolerant design hasconstellation and instrument redundancy

D2

925

-10

@ C

CA

S

Instrument I&TUCB

Mission I&TSwales

Encapsulation

& launch

BGS

OperationsUCB

Probe instruments:ESA: Thermal plasmaSST: Super-thermal plasmaFGM: Low frequency B-fieldSCM: High frequency B-fieldEFI: Low and high frequency E-field

Ground

SST

ESA

EFIa

EFIs

FGM

SCM

Tspin=3s


Identical instrumentation provides high science margins and fault tolerance

• Instrument redundancy:– SST-ESA energy

overlap– FGM-SCM frequency

overlap– P1/P2 redundant

instrumentation (only directional flux needed in one of two).

• Each probe has:FGMESA2SSTh (2heads)SCM2EFIa (2axials)4EFIs (4spin plane)

Selected instruments built en masse

Instruments required to achieve Primary Mission Objective

Measurement goals P1 P2 P3 P4 P5

Tim

e H

istory o

f Eve

nts

P3,4&5 monitor CDP1,2 bracket Rxtres<30s, Y<±2RE

FGM

2SSTh

2EFIs

FGM

ESA

2SSTh

2EFIs

FGM

ESA

1SSTh

FGM

ESA

1SSTh

FGM

ESA

1SSTh

Ma

crosca

le In

tera

ction

s

Track rarefaction wave, inward flows, Poynting with B<1nT, V/V~10%

FGM

ESA

FGM

ESA

FGM

ESA

FGM

ESA

Radial/cross-sheet pressure, velocity and current gradients require P/P~ V/V ~ B/B ~10%, non-MHD

FGM

ESA

FGM

ESA

2EFIs

FGM

ESA

2EFIs

FGM

ESA

2EFIs

Cross-tail pairs measure FLRs, KH, ballooning on B, V, P @ 10s and fast modes on Bxyz and Exy @ 6Hz

FGMESA SCM

FGMESA SCM 4EFIs2EFIa

FGM ESA

2EFIs

FGM ESA SCM 4EFIs2EFIa


Mission profile is robust

Pre-Launch

(6hrs)

Launch

(25min)

Check-out & ascend

(60days)

Science ops

(2yrs)

Re-entry

•Checkout•Countdown

•2nd stage burn•Spin-up•3rd stage burn•Spin-down

• Probe dispense • Bus check-out• Dply mags/check instr.• Orbit place. Total of: - 6 side thrustings

- 6 reor/fire/reor sequences

• Deploy EFI

•Minor ctrl ops (all):– 22 side-thrustings– 2 inclination changes

•M

ino

r ctrl op

s (Sid

e-th

rusts, fin

ish b

y EO

M+

9m

o)

- 8 sid

e-thru

stings

• P

assive

re-e

ntry th

ere

afte

r (1-1

0yrs)

• Fuel consumption, maneuvers and contacts during ascend:

validated with GMAN.


First bonus: What producesstorm-time “killer” MeV electrons?

Affect satellites and humans in space

Source:

– Radially inward diffusion?

– Wave acceleration at radiation belt?

THEMIS:

–Tracks radial motion of electrons

•Measures source and diffusion

•Frequent crossings

–Measures E, B waves locally

ANIK telecommunicationsatellites lost for days to weeks

during space storm


Second bonus: What controls efficiencyof solar wind – magnetosphere coupling?

Important for solar wind energy transfer in Geospace

Need to determine how:– Localized pristine solar wind features…

– …interact with magnetosphere

THEMIS:

– Alignments track evolution of solar wind

– Inner probes determine entry type/size


Mission design meets requirements

Mission profile– Two year mission design easily met in this high Earth orbit

– Launch: D2925 from CCAS (40min window any day)

– Simple probe carrier (3rd stage fixture) w/ release built by an experienced team

– Science & routine ops and multi-object tracking has ample heritage at UCB

– Simple RCS, heritage sfw & ground-cmd and GSFC/GNCD support benefits MOC

Probe design– Simple, passive thermal design w/ thermostatically controlled backup heaters

– Survival at all attitudes under worst shadow conditions

– Simple data flow / automated routine science ops minimize cost and risk• Store/Forward 375Mbit/orbit (256Mbyte capability permits multi-orbit storage)

– Orbit control & knowledge exceed placement rqmts by factor of 10

– Early EMC/ESC mitigation as per heritage practices (e.g. FAST, POLAR)


Active trade studies constantly reduce risk

Phase A main trade studies:Direct inject with passive PCA reduces schedule and ops risks

PCA dispense simplified: improves clearances, reduces risk

Increased fuel tank capacity

Added solar panels at bottom face

ACS solution simplified with micro-gyros replacing accelerometers

Connected RCS propulsion pods

Phase B main trade studies:Exercised alternate path for SST instrument

Tuned Phase A orbit design to reduce differential precession; enhanced 2nd year science products

Changed BAU processor to reduce software complexity motivated by GSFC experience

Increased tank size to take full advantage of mass to orbit capability, yet at lower cost

Increased thruster size to reduce finite arc inefficiency and Msn Ops complexity

Repackaged SST and SCM electronics along with IDPU

Removed ESA attenuator (simplified instrument) with minimal effect on bonus science

Included redundant actuators and surge protection in instrument designs

An integrated team of scientists and engineers constantly optimize mission design and resources, reducing risk.


Descope list and science-relatedrisk mitigation factors

Can do baseline science even after inadvertent complete instrument failures

Re-positioning allows recovery from failure of critical instruments on some probes

Graceful degradation results from partial or even full instrument failures– Instrument frequency and energy range overlaps– Complete backup option for EFI radials (need 2 in most probes but have 4)– Relaxed measurement requirements (1nT absolute is not permitted to drive team, but rather a nicety)– Substorms come in wide variety; can still see large ones with degraded instruments

Minimum mission can be accomplished with a reduced set of spacecraft requirements– EMC and ESC requirements important for baseline but less severe for minimum mission– Observation strategy can be tuned to power loss (turn-on/off) and thermal constraints (tip-over/back)– Fuel and mass margins for 1st year (minimum) are 30% larger than for a two year (baseline) mission


Minimum mission providesdefinitive answer to the substorm question.

P1P2P3P4P5• Simultaneous observations in the key regions

• Ideal geometries for tens of substorms

• Data rates / time resolution exceed requirements

• Analysis tools available from Cluster, ISTP, FAST

• Experienced co-Is are leaders

on both sides of substorm controversy

• Minimum mission accomplished within 8 months

from nominal launch date


THEMIS Mission Overview

Peter R. Harvey

Project Manager

Space Sciences Laboratory

University of California, Berkeley


Salient Features

Science– Purpose

To understand the onset and macroscale (1-10 Re) evolution of magnetospheric substorms.

– CapabilitiesWill provide the first measurements of substorm starting locationWill provide the first measurements of substorm evolution

– Collaborating Institutions

University of California (UCB, UCLA)Swales Aerospace Inc. (SAI)Goddard Space Flight Center (GSFC)University of Colorado (LASP)Technical University of Braunschweig (TU-BS)Institut fur Weltraumforschung der OAW (IWF)CETP

CESRUniversity of CalgaryUniversity of AlbertaNOAAUniversity of Saint PetersburgTokyo Institute of Technology


Salient Features

Mission Parameters– Launch

Vehicle: Delta II, Eastern RangeInjection: 1.1 x 12 Re, 9 degrees inclinationDate: August 2006 ( unrestricted )

– Space SegmentSpacecraft: 5 Spinning probes with fuel for orbit/attitude adjustOrbit Period(s): 1, 2 and 4 daysOrientation: Ecliptic normal

– Ground SegmentObservatories: 20 Stations for All Sky Imaging and Mag Field

– OperationsPhases: L&EO (2 mo), Campaigns (Dec-Mar), De-

OrbitLifetime: 2 years


Standard Delta 10 ft. Fairing Static Envelope

3712 PAF

Probe Carrier Assembly (PCA = 5 Probes + Probe Carrier) on L/V

Probe Carrier Assembly (PCA = 5 Probes + Probe Carrier) on L/V

THEMIS Launch Configuration

THEMIS Launch Configuration

Probe Carrier Assembly (PCA) on Delta 3rd StageProbe Carrier Assembly (PCA) on Delta 3rd Stage

Launch Configuration

Dedicated launch accommodated within standard Delta 7925-10 vehicle configuration and services

10’ Composite Fairing required to accommodate five Probes on the Probe Carrier in the “Wedding Cake” configuration

PC stays attached to Delta 3rd stage after probe dispense

Each probe dispense from the PCA is coordinated with but independent of the other probes

No single probe anomaly precludes dispense of remaining probes

Star 48 3rd Stage


Probe Bus Design

Power positive in all attitudes with instruments off (launch, safe hold modes)

Passive thermal design using MLI and thermostatically controlled heaters tolerant of longest shadows (3 hours)

– Spin stabilized probes orbit within 13° of ecliptic plane have inherently stable thermal environment

S-Band communication system always in view of earth every orbit at nominal attitude. In view for greatest part of orbit in any attitude

Passive spin stability achieved in all nominal and off-nominal conditions

Monoprop blow down RCS (propulsion) system is self balancing on orbit


Instrument Payload


PAF Adapter Ring/Tube & Attach to Launch Vehicle

PAF Adapter Ring/Tube & Attach to Launch Vehicle

Main DeckMain Deck

Center SpoolCenter Spool

(4) Lower Probe

Standard Separation

Fittings

(4) Lower Probe

Standard Separation

Fittings

(1) Upper Probe Standard Separation Fitting(1) Upper Probe Standard Separation Fitting

(8) External Struts(8) External Struts Probe Carrier (PC)Probe Carrier (PC)

Probe Carrier Design

Simple probe carrier utilizes– Machined aluminum structure– Standard heritage payload attach fittings

for Probes utilize pyro- actuated clampband– Straight-forward umbilical interconnect

harness– Multi layer insulation blanketing as required

Detailed design supported by comprehensive analysis– NASTRAN model used to recover material

stresses and fundamental frequencies– Base drive analysis used to verify strength

and recover component loads– Preliminary Coupled Loads Analysis

completed for our Delta II ELV

Probe layout on carrier maximizes static and dynamic clearances– Design is the best balance between

deployment clearances and probe structural mass

First Axial Mode: 48.27 Hz

First Lateral Mode:18.29 Hz

Probe Carrier Fundamental Natural Frequencies:

Displacements Not to Scale


ADAMS Dispense Model Dynamic Simulation Image

ADAMS Dispense Model Dynamic Simulation Image

Split screen

Probe Separation

Design study and analysis results– Deploy sequence of P1 then P2-P5 simultaneously– 15 rpm nominal PCA spin rate– Probe separation velocity of .35 m/s

Results of evaluating off-nominal conditions– No collisions or close approaches due to combinations

of ‘stuck’ Probes, timing errors and tip-off– Reasonable nutation and pointing angles that

Probe ACS can easily accommodate– Separation initiation is two fault tolerant

Visualization– Used actual output files from ADAMS to make

the animation

Flexibility for tuning deployment later in the design process includes; carrier spin rate, deployment spring stiffness, deployment order, and timing


Ground System Block Diagram


Resource Not to Exceed (NTE)

Current Best Estimate (CBE)

Margin

Probe Carrier Assembly Dry Mass (kg) 606.5 1 458.4 32.3%

Delta V (m/s) 700 574 21.9%

Orbit Average EOL Power (W) 38.2 28.1 35.8%

Science Data Storage (MB) 256 187.5 2 36.5%

Probe TLM Data Storage (MB) 16 11 45.5%

Notes: 1. Probe Carrier Assembly Dry Mass NTE = LV Capability (800 kg) - 5 x Fuel (38.7 kg) = 606.5 kg2. Current Best Estimate 750Mbits/orbit + 1 day contingency = 1500Mbits = 187.5MB

RF Link Margin

- Science Downlink (1024 kbps at perigee) 4.2 dB

- H&S Downlink (4 kbps at apogee) 6.0 dB

- Command Uplink (1 kbps at apogee) 6.2 dB

System Margins


Power Generation

Power Margin and Current Best Estimate History since PDR

– Issues identified after PDR dropped potential power generation capability of baseline design significantly

– Solutions have been identified and are being implemented

PDR December Current Design

EOL Power 42.6 34.4 38.2

CBE 27.3 30.2 28.1

Margin 56.1% 13.7% 35.8%


Power Generation

Work-around Effect Notes

Extra cells +5.1% Conservative 3 strings lost due to Mag Booms, 1 string loss > 60 deg due to EFI Snout.

Increased area

+9.4% A number of layouts are being evaluated. Increased area represents most conservative option to date. No mass increase anticipated.

Issues Identified since PDR

– Effect of shadowing from EFI Snout and Mag Booms greater than expected

– Losses due to Electrostatic Cleanliness (ESC) Implementation (ITO coating and interconnects) greater than anticipated

– Cell cosine loss assumptions were more optimistic at PDR than actual data

– PDR calculation assumed power would be produced at higher incidence angle than current specification

Solutions being implemented– Added cells around EFI snout to mitigate shadowing– Increased total photon collecting area

Issue Effect

Shadowing -14%

ESC -7%

Cosine loss -2.9%

Incident angle -5.7%


Organization

Mission Manager Frank Snow, GSFC

Mission Manager Frank Snow, GSFC

Financial MgrK. Harps, UCBFinancial MgrK. Harps, UCB

Launch Vehicle G. Skrobott, KSC

Launch Vehicle G. Skrobott, KSC

Project Scientist D. Sibeck, GSFC

Project Scientist D. Sibeck, GSFC

THEMIS PI V. Angelopolous, UCB

THEMIS PI V. Angelopolous, UCB

Project Manager P. Harvey, UCB

Project Manager P. Harvey, UCB

Science Co-I’s Science Co-I’s EPO N. Craig, UCB

EPO N. Craig, UCB

SubcontractsJ. Keenan, UCBSubcontracts

J. Keenan, UCBScheduling

D. Meilhan, UCBScheduling

D. Meilhan, UCBQuality Assurance

R. Jackson, UCBQuality Assurance

R. Jackson, UCB

Mission Systems

E. Taylor, UCB

Mission Systems

E. Taylor, UCB

Mechanical/ Thermal Systems

P. Turin, UCBC. Smith, UCB

Mechanical/ Thermal Systems

P. Turin, UCBC. Smith, UCB

Mag Cleanliness

C. Russell, UCLA

Mag Cleanliness

C. Russell, UCLA

Probe/Probe CarrierManagement

UCB Oversight: D. KingSwales Mgr: M. Cully

Probe/Probe CarrierManagement

UCB Oversight: D. KingSwales Mgr: M. Cully

Instruments

P. Berg, UCB

Instruments

P. Berg, UCB

Ground Segment

M. Bester, UCB

Ground Segment

M. Bester, UCB

Software Systems

D. King, UCB

Software Systems

D. King, UCB

Mission I&T

R. Sterling, UCB

Mission I&T

R. Sterling, UCB


Organization

Instrument Development

InstrumentsP. Berg

InstrumentsP. Berg

Electric Field Instrument

(EFI)J. Bonnell

Electric Field Instrument

(EFI)J. Bonnell

ElectroStaticAnalyser

(ESA)C. Carlson

ElectroStaticAnalyser

(ESA)C. Carlson

Solid StateTelescope

(SST)D. Larson

Solid StateTelescope

(SST)D. Larson

InstrumentData Processor

Unit (IDPU)M. Ludlam

InstrumentData Processor

Unit (IDPU)M. Ludlam

FluxgateMag

(FGM)U. Auster

FluxgateMag

(FGM)U. Auster

Search CoilMag

(SCM)A. Roux

Search CoilMag

(SCM)A. Roux

Forrest MozerGreg DeloryArt HullBill DonakowskiGreg DaltonRobert DuckMark PankowDan SchickeleStu HarrisHilary Richard

Forrest MozerGreg DeloryArt HullBill DonakowskiGreg DaltonRobert DuckMark PankowDan SchickeleStu HarrisHilary Richard

Robert AbiadPeter BergHeath BerschDorothy GordonFrank HarveySelda HeavnerJim LewisJeanine PottsChris ScholzKathy Walden

Robert AbiadPeter BergHeath BerschDorothy GordonFrank HarveySelda HeavnerJim LewisJeanine PottsChris ScholzKathy Walden

M. MarckwardtBill ElliottRon HermanChris Scholz

M. MarckwardtBill ElliottRon HermanChris Scholz

Robert LinDavin LarsonRon CanarioRobert LeeT. Moreau

Robert LinDavin LarsonRon CanarioRobert LeeT. Moreau

Hari DharanY. KimTien TanBill Tyler

Hari DharanY. KimTien TanBill Tyler

TUBS/IWFUli AusterK.H. GlassmeierW. Magnes

TUBS/IWFUli AusterK.H. GlassmeierW. Magnes

CETPAlain RouxBertran de la PorteOlivier Le ContelChristophe CoillotAbdel Bouabdellah

CETPAlain RouxBertran de la PorteOlivier Le ContelChristophe CoillotAbdel Bouabdellah

LASPRobert ErgunAref NammariKen StevensJim Westfall

LASPRobert ErgunAref NammariKen StevensJim Westfall

MagBoomsMag

Booms


Organization

Ground Systems Development

Ground SegmentGround Segment

Mission Ops Science Ops

(Mission Planning)

Mission Ops Science Ops

(Mission Planning)

Ground Based ObservatoriesGround Based Observatories

Manfred BesterMark LewisTim QuinnSabine FreyTai PhanJohn BonnellLaura Peticolas

Manfred BesterMark LewisTim QuinnSabine FreyTai PhanJohn BonnellLaura Peticolas Stephen Mende

Stu HarrisSteve GellerHarald Frey

Stephen MendeStu HarrisSteve GellerHarald Frey

UCLAChris RussellJoe MeansDave Pierce

UCLAChris RussellJoe MeansDave Pierce

All Sky ImagersAll Sky Imagers

Ground Magnetometers

Ground Magnetometers

Fielding & Operation

(UC&UA)

Fielding & Operation

(UC&UA)

UCEric DonovanUCEric Donovan

GSFC/GCNDDavid SibeckMark BeckmanBob DeFazioDavid FoltaRick Harman

GSFC/GCNDDavid SibeckMark BeckmanBob DeFazioDavid FoltaRick Harman

UAJ. SamsonUAJ. Samson


Agreements

Contracts & Agreements Status

Agreement Role Status Swales Probes and Probe Carrier Subcontract Negotiations Ongoing

LASP EFI - Digital Fields Board Design Subcontract in place CETP SCM - Search Coil Magnetometer

and Preamps LoA Signed by Code S is at Code I

TU-BS FGM - Fluxgate Magnetometer Sensors

LoA Signed by Code S is at Code I

IWF FGM - Fluxgate Magnetometer Electronics


UCLA Ground Based & EPO Magnetometers Spacecraft EMC expertise

Subaward in place

University of Calgary

Ground Based Observatory Site Development and Operations


University of Alberta

Ground Based Observatory Site Development and Operations



60 days Funded Schedule Reserve Included


Schedule

Key Features

Instrument Development– EM Instrument I/F Testing with EM Probe I/F– Integrate Instrument Complement at UCB Prior to S/C Integration– Instrument Complement F1 Tested First Followed by Pairs– All Instrument Complements are Complete before S/C I&T Begins– Instrument I&T Team Will Be Focusing Upon S/C I&T– Added Some Facilities for Qualifying Instruments in Parallel

Spacecraft Development– Integration and Test of Probe1 Completed Prior to Probes 2-5– Sufficient Manpower and Equipment for Parallel I&T

Ground Development– Development and Deployment of 5 GBOs 2 in 1Q05– Development and Deployment of all 20 GBO’s in 1Q06


Schedule

Metrics

Milestone Comparisons to HESSI

Sufficient Definition– 23 Schedules involving 3977 tasks

Slack– Instruments have 4.5-6 months slack to Earliest I&T with Probes– Instruments have 6.5-9.5 months slack to Expected I&T with Probes– Integrated Probes/Probe Carrier have 2 months to LV Integration

Activity THEMIS PLAN

HESSI ACTUAL

%

Start to PDR 5 mo 4 mo 125% PDR to CDR 6 mo 4 mo 150% CDR thru S/C#1 I&T 12-15 mo 15 mo 80-100% Start thru S/C#1 I&T 24-27 mo 23 mo 104-117% Probe 2 to 5 I&T (ea) 2.5 mo 1.5 mo 166%


Schedule

Relevant Prior Schedule Performance

FAST Instruments (EFI, ESA, MAG, IDPU)– Hopped in Front of SWAS– Delivered Complement on Time

POLAR / CLUSTER I & II (EFI)– Polar EFI Delivered 8 months ahead of time– Cluster EFW I & II Delivered > 45 Flight Units to WEC in time.

HESSI (Management, IDPU)– Phase B to JPL Environmental Tests (Est. 23 mo, Act. 23.2 mo)– Re-Confirmation to VAFB Delivery (Est. 6 mo, Act 6.3 mo)


Schedule

Component Source Minimal Changes to Unit ImpactsEFI-SPB Cluster II Moved Electronics to IDPU, Changed to

Right Angle Drive, SMA instead of PyroMass savings

EFI-AXB FAST Shorter, Moved Electronics to IDPU, SMA instead of Pyro

Mass and Stability

ESA(I) FAST IESA Anode locations rearranged to better respond to cold SW and hot tail. Cover release changed from meltwire to SMA.

Added 50 grams

ESA(e) FAST EESA Reduced number of anodes from 16 to 8 Mass savingsSST WIND SST Packaged electronics in IDPU for radiation

shielding.Mass & Power savings

SCM Interbal Sensor None NoneCluster PA Improved packaging & rad tolerance. Mass savings

FGM ROMAP Computer Interface NoneSCM-Boom FAST Single Element, No Mid-Hinge. SMA

instead of PyrotechnicSimpler

FGM-Boom FAST Horizontal Orientation, Mid-Hinge, SMA instead of Pyrotechnic

Simpler

Instrument Heritage Maintained thru PDR


Cost

Cost Estimate (src CSR Figure3)Cost Element FY02 FY03 FY04 FY05 FY06 FY07 FY08 RY FY02Phase A 0.450 0.000 0.000 0.000 0.000 0.000 0.450 0.450 Concept Development 0.450 0.450 0.450Phase B 0.000 6.740 4.221 0.000 0.000 0.000 10.962 10.551 Preliminary Design 6.740 4.221 10.962 10.551Phase C/DInstruments 0.000 0.000 4.970 2.472 1.053 0.000 0.000 8.494 7.920Spacecraft 0.000 0.000 12.037 13.668 5.580 0.000 0.000 31.285 28.968

Proj Mgmt/Sys Eng 1.155 1.604 1.323 1.084 5.165 4.829Science Team Support 0.303 0.400 0.420 1.280 2.403 2.206Prelaunch Ground System 0.453 1.232 1.819 1.702 5.206 4.805EPO 0.008 0.381 0.310 0.191 0.889 0.824NASA - CTV,IVV 0.065 0.204 0.311 0.229 0.809 0.748

Subtotal - Phase C/D 0.000 1.984 20.827 20.322 11.118 0.000 0.000 54.251 50.300Reserves 8.250 4.125 4.125 16.500 15.297

Total Phase C/D 0.000 1.984 29.077 24.447 15.243 0.000 0.000 70.751 65.597Phase E

MO&DA 6.952 6.765 13.718 11.788NASA DSN, TDRSS 0.207 0.130 0.336 0.290E/PO, Other 0.194 0.189 0.383 0.329

Subtotal Phase E 0.000Reserves 0.000 0.000 0.000 0.000

Total Phase E 0.000 0.000 0.000 0.000 0.000 7.353 7.084 14.437 12.407Launch Services 0.000 1.000 11.000 31.000 29.000 4.000 0.000 76.000 69.368

Total NASA OSS Cost 0.450 9.724 44.299 55.447 44.243 11.353 7.084 172.600 158.374


Cost

Cost ReasonablenessTHEMIS Phase B/C/D Costs Compare Well to HESSI Actual Costs– THEMIS Instruments Require Less Development than HESSI

THEMIS Phase E Mission Operations Suitably Larger– Handling 5 Probes Instead of 1; Cost Estimated at 3x

PHASE B/C/D ELEMENTS THEMIS HESSI1. Mgmt, Sci, Sys 11.6% 11.8%2. Space Segment 78.5% 78.4%2.1. Instrumentation 22.4% 30.4%2.2. Spacecraft 56.1% 48.1%3. Ground Segment 8.0% 9.8%4. MODA - -5.0 Education / Public Outreach 1.9% included

PHASE E ELEMENTS THEMIS HESSI T.v.H4.1. Mission Operations 31% 18% 3.04.2. Data Analysis 69% 82% 1.5Total 1.8


Cost

Relevant Prior Cost PerformancePOLAR / CLUSTER I & II (EFI)– Polar EFI Delivered at 37% Under Budget– Cluster EFW I Delivered 40% Under Budget. – Cluster EFW II Was Built using Reserve from EFW I

HESSI (Management, IDPU)– Completed Spacecraft & Ground Systems at 8% Under Budget– Re-Built Spacecraft 39% Under Budget

HESSI UCB Actual Cost v Plan

Bud-Acc

Act-Acc

Act+Liens

Bud-Acc

Act-Acc

Act+Liens


Cost

Total Project Cost Performance v Budget

$0

$2,000,000

$4,000,000

$6,000,000

$8,000,000

$10,000,000

$12,000,000

$14,000,000

$16,000,000

$18,000,000

$20,000,000

ThruApril '03

May '03 June '03 July '03 August '03 September '03 October '03 November '03 December '03


Summary

SummaryExperienced Teams are In Place

Management, Systems Engineering, Quality Assurance(HESSI, Chips, EUVE, Image, FAST, Cluster, Polar, Firewheel,…)

Cost is ReasonableCompares to Prior Missions, On-Budget thru Phases A/B

Schedule is Consistent with Previous ProjectsHESSI, Polar, Cluster


BACKUP SLIDES


Baseline L1 Requirements

S-1 Substorm Onset Time– Determine substorm onset time and substorm meridian magnetic local time (MLT) using ground

ASIs (one per MLT hr) and MAGs (two per MLT hr) with t_res<30s and dMLT<1 degree respectively, in an 8hr geographic local time sector including the US. (M-11, GB-1)

S-2 Current Disruption (CD) Onset Time– Determine CD onset time with t_res<30s, using two near-equatorial (within 2Re of magnetic

equator) probes, near the anticipated current disruption site (~8-10 Re). CD onset is determined by remote sensing the expansion of the heated plasma via superthermal ion flux measurements at probes within +/-2Re of the measured substorm meridian and the anticipated altitude of the CD. (M-9, IN.SST-1, IN.SST-4, IN.FGM-1)

S-3 Reconnection (Rx) Onset Time– Determine Rx onset time with t_res<30s, using two near-equatorial (< 5Re from magnetic equator)

probes, bracketing the anticipated Rx site (20-25Re). Rx onset is determined by measuring the time of arrival of superthermal ions and electrons from the Rx site, within dY=+/-2Re of the substorm meridian and within <10Re from the Rx altitude. ….. (M-9, IN.EFI-2, IN.ESA-1, IN.SST-2, IN.SST-3, IN.SST-4, IN.FGM-1)

S-4 Simultaneous Observations– Obtain simultaneous observations of: substorm onset and meridian (ground), CD onset and Rx

onset for >10 substorms in the prime observation season (September-April). Given an average 3.75hr substorm recurrence in the target tail season, a 2Re width of the substorm meridian, a 1Re requirement on probe proximity to the substorm meridian (of width 2Re) and a 20Re width of the tail in which substorms can occur, this translates to a yield of 1 useful substorm event per 18.75hrs of probe alignments, i.e, a requirement of >188hrs of four-probe alignments within dY=+/-2Re. (M-1, M-12, IN.FGM-1)


S-5 Earthward Flows– Track between probes the earthward ion flows (400km/s) from the Rx site and the tailward moving

rarefaction wave in the magnetic field, and ion plasma pressure (motion at 1600km/s) with sufficient precision (dV/V=10% or V within 50km/s whichever is larger, dB/B=10%, or B within 1nT whichever is larger, dP/P=10%, or P within 0.1nPa whichever is larger) to ascertain macroscale coupling between current disruption and reconnection site during >10 substorm onsets (>188hrs of four-probes aligned within dY of +-2Re). (IN.ESA-1, IN.SST-3, IN.FGM-1)

S-6 Pressure Gradients– Determine the radial and cross-current-sheet pressure gradients (anticipated dP/dR, dP/dZ

~0.1nPa/Re) and ion flow vorticity/deceleration with probe measurement accuracy of 50km/s/Re, over typical inter-probe conjunctions in dR and dZ of 1Re, each during >10 onsets. The convective component of the ion flow is determined at 8-10Re by measurements of the 2D electric field (spin-plane to within +-30degrees of ecliptic, with dE/E=10% or 1mV/m accuracy whichever is larger) assuming the plasma approximation at t_res<30s. (IN.EFI-1, IN.ESA-1, IN.ESA-2, IN.SST-3, IN.FGM-1)

S-7 Cross-Current Sheet changes– Determine the cross-current-sheet current change near the current disruption region (+/-2Re of

meridian, +-2Re of measured current disruption region) at substorm onset from a pair of Z-separated probes using the planar current sheet approximation with relative (interprobe) resolution and interorbit (~12hrs) stability of 0.2nT. (IN.FGM-1, PB-42, PB-43, PB-44)

S-8 non-MHD plasma– Obtain measurements of the Magneto-Hydrodynamic (MHD) and non-MHD parts of the plasma

flow through comparisons of ion flow from the ESA detector and ExB flow from the electric field instrument, at the probes near the current disruption region, with t_res<10s. (IN.EFI-1, IN.ESA-1, IN.SST-3, IN.FGM-1)

… continued: Baseline L1 Requirements


S-9 Cross-Tail Pairs– Determine the presence, amplitude, and wavelength of field-line resonances, Kelvin-Helmholz

waves and ballooning waves on cross-tail pairs (dY=0.5-10Re) with t_res<10s measurements of B, P and V for >10 substorm onsets. (IN.ESA-1, IN.SST-3)

S-10 Cross-Field Current Instabilities– Determine the presence of cross-field current instabilities (1-60Hz), whistlers and other high

frequency modes (up to 600Hz) in 3D electric and magnetic field data on two individual probes near the current disruption region for >10 substorm events. (IN.EFI-3, IN.ESA-3, IN.SCM-1)

S-11 Dayside Science– Determine the nature, extent and cause of magnetopause transient events (on dayside). (IN.ESA-4,

IN.SST-6)

… continued: Baseline L1 Requirements


Minimum L1 Requirements (from L1’s)

4.1.2.1 Substorm Onset Time– Determine substorm onset time and substorm meridian magnetic local time (MLT) using ground MAGs (at

least one per MLT hr) with t_res<30s and dMLT<6 degrees respectively, in a 6hr geographic local time sector including the US.

4.1.2.2 Current Disruption (CD) Onset Time– Determine CD onset time with t_res<30s, using two near-equatorial (within 2Re of magnetic equator)

probes, near the anticipated CD site (~8-10 Re). …(same as baseline)

4.1.2.3 Reconnection (Rx) Onset Time– Determine Rx onset time with t_res<30s, using two near-equatorial (<5Re of magnetic equator) probes,

bracketing the anticipated Rx site (20-25Re). … (same as baseline)

4.1.2.4 Simultaneous Observations– Obtain simultaneous observations of: substorm onset and meridian (ground), CD onset and reconnection

onset for >5 substorms in the prime observation season (September-April). Substorm statistics discussed in S-4 point to a requirement of >94hrs of four probe alignments.

4.1.2.5 Energetic ion and electron fluxes– SST to measure near the ecliptic plane (+/-30o) superthermal i+ and e- fluxes (30-100keV) at t_res<30s.

4.1.2.6 Earthward Flows– Track between probes the earthward ion flows (400km/s) from the reconnection site and the tailward moving

rarefaction wave in the magnetic field, and ion plasma pressure (motion at 1600km/s) with sufficient precision precision (dV/V=10% or V within 50km/s whichever is larger, dB/B=10%, or B within 1nT whichever is larger, dP/P=10%, or P within 0.1nPa whichever is larger) to ascertain macroscale coupling between current disruption and reconnection site during >5 substorm onsets.


Instrument Cost

Instrument Mass .v. Cost Modeling– Categorized Each Component by its Complexity

• EBOX : Electronics Box (src EFI & HESSI)• MECH : Mechanism with Few Electronics Parts (src Cluster)• SENSOR : Mixed Mechanical and Electronic Parts (src FAST)

– Computed Mass of Flight & Spare Units• Grass Roots Budget is 6% Over Model So Budget is Sufficient

UNIT Kg Units Total Model K$/Kg Estimate Budget RelIDPU (& up196) 4.0 6 23.9 EBOX 230 5506 5369 -3%EFI 11.2 6 67.3 MECH 50 3366 3874 13%ESA 2.1 6 12.5 SENSOR 165 2059 2110 2%SST 1.3 6 7.6 SENSOR 165 1247 1600 22%FGM Boom 1.2 6 7.2 MECH 50 360 349 -3%SCM Boom 0.5 6 3.0 MECH 50 426 427 0%


Instrument Cost

Heritage Instruments Costs .v. THEMIS– Typical NASA Instrument Contracts Have Greater Scope of Effort

• Science, Management, Systems Engineering, Quality Assurance• Mission Operations and Data Analysis• Significant Instrument Design and Development• Instrument Sensors• Instrument Main Electronics • Instrument Flight Software

– THEMIS Sensor Costs• Include Engineering for Interface-driven Modifications• Include Sensor Fabrication and Test in Quantity• Other Efforts are Costed in WBS 1 (Science, Management, Systems

Engineering, Quality Assurance), WBS 2.1.1 (IDPU, FSW), WBS 4 (MODA)


Descope Cost

Available Descope OptionsModest Requirements Allow Flexibility in Instrumentation

Cost Savings are Available

Required InstrumentProbe/Instrument P1 P2 P3 P4 P5 P1 P2 P3 P4 P5

FGM * * * * * * * * x *ESA x * * * * x * * x *SST (2 heads) 2 2 1 1 1 2 2 1 x 1SCM x x * x * x x x x xEFI Axials (2) x x 2 x 2 x x x x xEFI Spin Plane (4) 2 2 4 2 4 2 2 2 x 2

Baseline Mission Minimum Mission

Descope Table Benefit Time Savings (~$M)EFI Axials Cost CDR 1.75GBO's (1/2) Cost CDR 0.75SCM Cost,Mass CDR 0.35Non-Prime Contacts Cost ORR 0.50

Total 3.35

Date post:	21-Jan-2016
Category:	Documents
Upload:	dina-rose
View:	215 times
Download:	0 times

THEMIS MCRR GSFC 2/4/2004 THEMIS Mission Confirmation Readiness Feb 4 2004.

Documents