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The Magnetospheric Constellation (MC)

Global Dynamics

of the Structured Magnetotail

Updated Synopsis of the

Report of the NASA Science and Technology Definition Team

for the Magnetospheric Constellation Mission

October 2004

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THE MAGNETOSPHERIC CONSTELLATION

(MC) mission, with its distributednetwork of in situ observing stations, isthe ultimate tool for unraveling themysteries of magnetospheric storage,processing, and release of solar windenergy. Forty years of studies with indi-vidual or widely separated spacecrafthave been illuminating but ultimatelyinconclusive in terms of understandingthe fundamental physics. It is as if wehad attempted to understand tropo-spheric dynamics using a single mobileweather station or, perhaps, since therehas been an international effort, one inevery nation. Given a thoughtful planfor deployment, each mobile stationwould record many intriguing phenom-ena and build suggestive statistical datasets, but these could never support afull, predictive understanding of such arichly nonlinear dynamical system.

To create a station network, the MC mis-sion will use three dispenser ships, eachcomparable in size and complexity to atypical magnetospheric spacecraft. Eachwill deploy ~10–12 spacecraft of the ST–5 class into nested elliptical orbits withcommon perigees and apogees rangingfrom 7–27 RE altitude, at an inclinationthat maximizes the time spent in theplasma sheet. The spacecraft will have

the typical spacing of ~2 RE. The sciencepayload will deliver magnetic field,plasma density, temperature and flow,and energetic particle angular distribu-tions, at 10 sec resolution, with low-fre-quency waves up to 100 Hz.

It might be argued that a key break-through in surface weather studies wasthe development of global imaging sys-tems, operating from space. Recently,imaging missions have demonstratedthe power of remote sensing of geo-space using a spectrum of electromag-netic wavelengths and fast neutralatoms. Moreover, the effectiveness of aclose formation of 3–4 spacecraft hasbeen clearly demonstrated for studyingthe nature of boundary layers and othernarrow structures in geospace. With acombination of imaging for large scalesand spacecraft clusters for the boundarylayers, why do we need a multipoint insitu station network in geospace?

The answer is that, important as bound-ary layers and the inner magnetosphereare in geospace, the domain of solarwind interaction is large, laced withelectromagnetic and particle flow fieldsthat cannot be imaged, and it is knownto contain important dynamics at scalesinaccessible to clusters of spacecraft,such as extended reconnection X lines,flow channels, and flow vortices. In thenear term, steps can be taken and con-siderable progress can be made usingwell-conceived, one-dimensional arraysof spacecraft, deployed along a radiusor an arc of longitude. However, physi-cal understanding of system dynamicsacross all scales will ultimately require atwo-dimensional station network ofspacecraft encompassing the principalregions of interaction between the solarwind and ionospheric plasmas. This isthe function of the MagnetosphericConstellation mission, which, owing tothe New Millennium ST–5 trailblazerand other studies summarized herein, isready to be implemented today.

ExecutiveSummary

Visualizing the magneto-spheric constellationmission with the help ofglobal simulations fromJ. Raeder. Inset is auroralimagery from a DMSPspacecraft.

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THIS IS A SHORT, UPDATED SYNOPSIS OF

the Science and Technology Defini-tion Team (STDT) report, The Magneto-spheric Constellation Mission: DynamicResponse and Coupling Observatory(DRACO). The original report (and oth-er relevant documents) is available athttp://stp.gsfc.nasa.gov/missions/ mc/docu-ments/. Our purpose here is, first, toclarify and refine the science focus ofthe Magnetospheric Constellation (MC)mission and to establish science priori-ties by which the anticipated productiv-ity of the mission can be evaluated, inlight of developments since the 2001 re-port was released. We also report onseveral refinements of the mission defi-nition that have come out of a series offour engineering studies performed bythe GSFC Integrated Mission DesignCenter (IMDC). These studies, based onthe ST–5 spacecraft bus, show that thereno longer are technology obstacles toovercome for this mission.

The magnetotail is a critical volume ofthe geospace environment wherein glo-bal circulation of magnetic fields andplasmas is regulated in response tochanging solar wind conditions. In it,impulsive localized flow bursts launchand dissipate, powerful electrical cur-rents form and evolve abruptly, andmagnetic energy is explosively convert-ed to particle energy. The fundamentalplasma process known as magnetic re-connection is thought to occur duringsubstorms, an important building blockof “space weather.” These are recurrentimpulsive energy releases that becomemore frequent during magnetosphericstorms. The scale, dynamism, and tur-bulent evolution of the magnetotailhave humbled our efforts to observeand understand it using individualspacecraft. The magnetotail magneticfields and plasmas do possess an un-derlying, slowly varying coherent struc-ture, but strongly turbulent flows and

Introduction

The flow field and plasmacurrent generated by theLyon–Fedder–MobarryMHD simulation of themagnetotail, during achannel-like flow burst.

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fields usually are large compared to themean field or flow. Thus, globally co-herent pictures of the system dynamicsbecome lost in the “noise” of individualmeasurements. Despite more than 30years of research with ever more so-phisticated instrumentation on everlarger and more complex spacecraft,fundamental questions concerning thedynamic response of the magnetotail re-main unanswerable. Accordingly, scien-tific progress has slowed. Intelligent,reasonable scientists cannot reach con-sensus on these issues, not for lack ofmodels and theories, but because of alack of relevant measurements. Neithercurrent single spacecraft, nor tight clus-ters of spacecraft, can fully resolve thesefundamental controversies.

To provide the first-ever two-dimension-al, time-evolving vector field andstreamline images of this important re-gion, MC will deploy a “constellation”of small spacecraft from a single launch-er. With resources of 20–25 kg and

15–18 W apiece, 30+ MC spacecraft willbe deployed in elliptical, equatorial or-bits with common perigee altitudes of 1RE and apogee altitudes distributed from7 to 27 RE, yielding mean interspacecraftseparation of ~2 RE. Enabling technolo-gies for MC have been developed for theST–5 Nanosatellite Constellation Trail-blazer mission of the New MillenniumProgram. MC is now ready for definitionand development.

Magnetospheric Constellation is the logi-cal outgrowth of a sequence of Explorerand STP missions, designed to exploreplasma transport and energy conversionprocesses over spatial sizes ranging fromthe distance to the Sun to the size of low-energy particle gyro-orbits. The Mag-netospheric Multiscale (MMS) missionwill focus on the smallest scale, micro-physical processes occurring within andnear magnetospheric boundary layers:magnetic reconnection, charged particleacceleration, and eddy turbulence. It willserve as the plasma physical “micro-

Visualizing magnetotaildynamics with the helpof the Lyon–Fedder–Mobarry global simula-tion, showing magneticfield lines, plasma flowfield, and plasma pres-sure. The highest speedEarthward flows are en-closed by the red surface.

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scope,” investigating scales too small tobe resolved by global circulation models.The THEMIS mission targets an align-ment of five spacecraft along a radius ex-tending into the magnetotail, for a one-dimensional view of the magnetotail, asubstantial advancement over the studyof complex phenomena using individualspacecraft. MC will establish a 2-D arrayof spacecraft both along and across the

The initial nested orbitsof the MC mission, withcoloring to indicate theinner, central, and outerfamily of orbits.

Key Question (1)How does the magneto-tail behave?

ScienceObjectives

magnetotail, designed to serve as a“meso/macroscope” that can truly “im-age” and make dynamic movies of mag-netotail vector fields. Ultimately, it willyield a new understanding on which weshall build a predictive science of next-generation magnetospheric meteorologyand forecast models, adding to our col-lective body of knowledge relating tocomplex nonlinear dynamical systems.

THE OVERARCHING OBJECTIVE OF THE MCmission is to determine how the

magnetosphere stores, processes, andreleases energy derived from the solarwind interaction, accelerating particlesthat supply the radiation belts. This isstill the central mystery of magneto-spheric physics. In the following sub-sections, we expand this objective inthree areas.

1. Magnetotail Dynamics

Recently, it has been shown that brightnightside auroral UV emission regionsevolve in every measurable relevantmanner exactly like avalanches in nu-merical models of self-organized criticali-ty (SOC). Such models describe thetransport of a conserved quantity from aregion where it is loaded into the systemto a region, usually a boundary, where itis unloaded. This transport is enabledonly at spatial locations where a local-ized instability is excited. If the modeldynamics are in the neighborhood of“criticality,” then intermittent, burstycascades of instability, usually called ava-lanches, result. These avalanches havethe defining property that no characteris-tic spatial, temporal, or energy scales canbe found in their distributions over theentire range of scales defined, at the highend, by the global scales of the systemand, at the low end, by the scale sizes as-

sociated with the localized instabilitymechanism; the avalanches are “scalefree.” The question seems unavoidable:Why should auroral UV emission re-gions behave in this manner?

The relationship of nightside auroralUV emissions to fast flows generated byreconnection in the plasma sheet is nowwell established. This relationship hasbeen known for decades in the case ofglobal substorm events and auroral ex-pansions. More recently, however, it hasbeen shown that even isolated localizedreconnection in the plasma sheet leadsinevitably to small auroral bright spots,even during otherwise geomagneticallyquiet periods. Bursty bulk flows (BBFs)and pseudo-breakups are similarly re-lated to auroral emissions at intermedi-ate scales. Reconnection events in theplasma sheet occur over large ranges ofspatial and temporal scales and producenightside auroral emission events oversimilarly broad ranges of scales.

The magnetotail loading and unloadingcycle, of magnetic flux or energy, plays acentral role in the substorm . The scale-free distributions of bright nightside au-roral emission properties, combinedwith the relationship of reconnection inthe plasma sheet to auroral emissions,shows that the unloading of magneticflux or energy in the tail is carried by

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constellation of spacecraft that the MCmission will provide.

2. Particle Acceleration

The plasma sheet is known to be asource of particles from which are gen-erated the variable components of theradiation belts. A framework for radia-tion belt dynamics has been establishedon the basis of missions like CRRESand Polar. However, there is alwaysgreat uncertainty concerning the truespatial, temporal, and energy distribu-tion of the “seed electrons,” having en-ergies of 20–500 keV, that are furtherenergized via transport into strongermagnetic field regions.

Transport of seed electrons occursthrough a combination of processes suchas Earthward convection, radial diffu-sion and local acceleration by substorminjections during dipolarization events.ULF waves are active in electron acceler-ation through mechanisms as diverse asdrift resonance, magnetic pumping, andtransit-time acceleration. VLF waves areinvolved in electron acceleration as wellas in precipitation and loss. The objec-tive of the MC mission will be to sort outthe relative importance of these variousprocesses in determining the seed popu-lations injected into the inner magneto-sphere from the plasma sheet. This is anessential element in developing radiationbelt models to predictive capability.

A constellation array of spacecraftshould provide simultaneous observa-tions of the plasma sheet and of the out-er radiation belt/ring current region.These observations will permit us to(1) compare the electron distribution asa function of radial distance and localtime and, using models, to distinguishbetween diffusive and convective ef-

avalanches of localized reconnectionevents, the temporal, spatial, and mag-nitude scales of which are distributeduniformly over broad ranges. Sub-storms, pseudo-breakups, and BBFs aremembers of a continuous distribution ofsuch manifestations of instability in themagnetotail.

It is the nature of scale-free avalanchingsystems that all scales are strongly cou-pled nonlinearly; they all play an impor-tant role in the unloading process. Sub-storm activity in the magnetotailinvolves all spatial scales ranging fromthose associated with localized fastflows, ~1–2 RE and possibly smaller, upto the largest scales that can be containedin the tail, as well as all temporal scalesranging from a few tens of seconds asdetermined from the auroral emissionstudies, up to several hours, the typicalsubstorm duration. To understand thesubstorm mechanism in the magnetotail,the plasma sheet must be observed overall of these spatial scales simultaneouslyand continuously. Only a constellation ofspacecraft that is distributed over theplasma sheet can accomplish this.

MC observations will be used to (1) de-termine the spatial distributions of re-connection and related fast flows in themagnetotail, (2) track the evolution ofthese distributions over the substormcycle and in response to changing solarwind conditions, (3) determine the re-quirements for the onset of the globalavalanche events called substorms,(4) reveal the plasma physical principlesthat lead to a scale-free avalanchingmagnetotail, and more. Thus, the funda-mental nature of activity in the magne-totail will be revealed by the distributed

Key Question (2)How are particlesaccelerated to formthe radiation belts?

Artist’s concept of thespacecraft and dispenserships stacked in thevehicle shroud.

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fects, (2) determine the acceleration re-sponse to interplanetary conditions andstructures, (3) determine the flux re-sponse to activity measures, includingstorm fields, wave power, and auroralactivity, (4) measure energetic particleprecipitation and loss rates throughoutthese regions, and (5) identify magneticfield or plasma boundaries in the re-gions, thereby determining the degreeand extent of magnetospheric coher-ence.

3. Dayside Magnetopause Science

The MC mission will provide observa-tions critical to determining the domi-nant mode of solar wind–magneto-sphere interaction at the daysidemagnetopause. A wide variety of mod-els has been proposed to account forthat interaction. Some models invokesteady processes such as reconnectionalong an extended neutral line or wide-spread diffusion induced by wave–particle interactions. Other models in-voke transient local processes such asthe Kelvin–Helmholtz instability orbursty reconnection driven by intrinsicmagnetopause instabilities. Still other

models invoke bursty merging orboundary waves triggered by the high-ly variable solar wind input (or the sig-nificant perturbations introduced intothe solar wind by processes occurringwithin the foreshock).

The signatures of each of the proposedmechanisms are well known. Reconnec-tion produces high-speed plasma flowson interconnected magnetosheath–magnetosphere magnetic field lines,whereas diffusion produces a low-latitude boundary layer on closed mag-netic field lines, the dimensions ofwhich grow with downstream distance.Bursty reconnection produces fluxtransfer events, or FTEs—bundles of in-terconnected magnetic field lines thatbulge outward into both the magneto-sheath and magnetosphere. The Kelvin–Helmholtz instability produces anti-Sunward-moving waves on the innerand outer edges of the low-latitudeboundary layer. Pressure pulses in thesolar wind drive waves that propagatedawnward or duskward across localnoon in accordance with the spiral/orthospiral IMF orientation.

The significance of each proposedmechanism depends on the amount ofmass, momentum, and energy it trans-fers to the magnetosphere as a functionof solar wind conditions. These parame-ters can, in turn, be estimated from theoccurrence patterns and spatial dimen-sions of the phenomena generated byeach mechanism. To date, the lack ofwidespread observations has precludedaccurate estimates. However, the Con-stellation array of spacecraft will pro-vide precisely the observations neededto make the estimates: simultaneousmagnetopause, magnetosheath, fore-shock, and solar wind observationsover a wide range of local times.

Sampling probability den-sity plot for the MC mis-sion with 30 spacecraft inthe orbits indicated.

Key Question (3)How does themagnetopause respondto the solar wind?

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Constellation observations will be usedto (1) compare the precisely determinedcharacteristics expected for each of theproposed interaction mechanisms withobservations, (2) determine occurrencepatterns as a function of solar wind con-ditions, (3) determine the longitudinalextent of individual phenomena,

MissionDesign

Mission Top-Level Requirements

The probability distribu-tion of nearest neighborspacings between thespacecraft.

(4) track their longitudinal motion, and(5) determine amplitudes in the directionnormal to the magnetopause. In conjunc-tion, these observations will provide adecisive answer to some of the mostlong-standing and controversial ques-tions in magnetospheric physics.

TO ACHIEVE ITS SCIENCE OBJECTIVES, MCmust have a mission lifetime of suf-

ficient duration to observe magnetotailbehavior during a variety of solar windconditions and at least a sampling oftypical solar wind disturbances, includ-ing co-rotating interaction regions andCoronal Mass Ejections (CMEs). The en-tire constellation should be put into or-bit with apogees in the local time range

around local dawn. Initial activationwould then be completed well in ad-vance of the rotation of the tail acrossthe Constellation orbit pattern as Earthorbits the Sun. This would produce, ear-ly in the mission, a pioneering but ancil-lary study of the dawn flank of the mag-netosphere and its interaction with themagnetosheath. A main mission phasewould follow as the Constellation pass-es through the center of the magnetotailover a period of roughly 4 months. This,in turn, would be followed by a study ofthe dusk flank and boundary layer in-teractions. All of these would occur dur-ing the first 6 months of operation andwould achieve the minimum successcriteria for the mission. Continued oper-ations over a subsequent year wouldproduce unprecedented studies of thedayside magnetopause, magnetosheath,bow shock, and foreshock regions. Withthe completion of this first dayside sci-

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Mission evolution ofthe number of space-craft within a modelplasma sheet duringthe first three missionpasses through themidnight plasmasheet.

ence phase, MC would be in positionfor a second pass through the tail begin-ning 1 year after launch.

MC must establish its spacecraft arrayin the magnetotail region from about7 RE to 27 RE in the nightside along theSun–Earth line, and across the magneto-tail east and west of the Sun–Earth lineby ~10 RE. This is based on the impor-tance of phenomena within the regionfrom geosynchronous orbit to beyondthe fast flow reversal associated withsubstorm activity, near 25 RE. Eccentricorbits with perigees near 1 RE providean optimal trade between orbit stabilityand economical transmission of com-mands and data. A set of orbits withapogees ranging from 7 to 27 RE willprovide all the coverage that is needed.Careful study of the constellation orbitoptions has been performed to deter-mine that 30 satellites will give ade-quate spatial coverage to achieve ap-proximately 2 RE mean spacing ofspacecraft with random orbital phases,when the constellation is placed at aninclination of 15°.

An innovative deployment plan hasbeen developed that uses modular de-ployer ships to place groups of 10–12satellites into separate orbital groups.The deployer ships are essentially pro-pulsion unit shells that are powered andcontrolled by the MC satellites, whichcontain all avionics, solar cell arrays,and software to accomplish this. Eachdeployment unit, with its payload of10–12 satellites, is comparable in massand volume to a single MMS spacecraft.Any of the identical satellites is capableof controlling the deployer, providinghigh redundancy. One satellite on eachdeployer is designated as the controllerand the rest serve as backups.

The use of multiple ships to independent-ly deploy spacecraft to the inner, central,and outer orbits provides a substantialenhancement of the propulsion efficiencyof the deployment. It also allows for dif-ferent parts of the constellation to havedifferent orbital characteristics, provid-ing additional flexibility. For example, bykeeping the eccentricities of the three or-bit families similar, differential preces-sion of the groups can be reduced.

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The MC magnetometer isbased on this ST–5magnetometer hardware.

THE SCIENCE MEASUREMENT OBJECTIVES

have not changed from those de-scribed in the 2001 MC STDT Report.However, substantial definition of theinstrumentation has been accom-plished. A magnetometer has been de-veloped, fabricated, and tested for theST–5 mission, including a lightweight

deployable boom. In addition, concep-tual designs have been developed forthe plasma velocity analyzer and ener-getic particles detector. Further, a studyis underway, under SECID support, thatwill better define a multisensor control-ler for all MC instruments. We provide

SciencePayload

brief descriptions of the instruments en-visioned below.

The ST–5 magnetometer (MAG) is a re-search-grade miniature vector magne-tometer provided by UCLA. It covers arange from 0–64000 nT with intrinsicnoise <0.1 nT RMS. Digital resolution is

better than 1 part in 5000. Resources are420 gm and 500 mW. The time resolu-tion available for wave spectral studiesis 100Hz.

The MC Plasma Velocity Analyzer(PVA) is conceptually a pair of half

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Payload Requirements

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The MC plasma velocityanalyzer is based on apair of conventional tophat analyzers with 180°field of view for electronsand ions.

The MC energetic parti-cle analyzer is based onconventional solid-statetelescope designs,arranged so as to forma 180° field of view forelectrons and ions.

DataSynthesis

(180° FOV, swept by spacecraft spin)top hat electrostatic analyzers packagedhead to head with entrance aperturesaligned to view through a commonspacecraft opening. In practice, the elec-tron analyzer may be smaller than theion analyzer, in view of larger typicalfluxes. Both analyzers are equippedwith automatic aperture control or sen-sitivity control to enable them to handlehigh magnetosheath fluxes encountered

when the spacecraft are outside themagnetosphere.

The MC Energetic Particle Analyzersimilarly provides a 180° (swept byspacecraft spin) field of view for bothelectrons and ions, based on a pair ofsensor units mounted at 45° to each oth-er. Each identical sensor element con-tains three electron and ion pixels, pro-viding six broad polar angle channels.

THE MAGNETOSPHERIC CONSTELLATION

mission will provide multipoint insitu magnetospheric measurements ofsubstantially greater quantity than anyprevious mission. Making optimal useof the measurements will require the de-velopment and application of new tech-

niques. The implementation of the MCmission will result in a leap, similar inits importance to the one made by at-mospheric physicists decades ago. Ini-tially, individual weather observationswere gathered into synoptic maps (sum-marizing a large number of individual

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observations). Later, the maps came tobe further processed using spatial objec-tive analysis and data assimilation.These techniques developed for theatmospheric sciences over the past de-cades can be borrowed to solve the newanalysis challenges of MC.

Assimilation of data can minimize er-rors in both the data and the model,even when the model suffers from sim-plifying assumptions, and thus providean optimal “map” of the physical stateof the magnetosphere at any given time.Data assimilation techniques have beensuccessfully used in atmospheric andoceanographic models for some time,but never before in magnetosphericmodeling. The primary reason that dataassimilation methods have not yet

found their way into magnetosphericmodeling is the scarcity of magneto-spheric in situ measurements. The MCmission will change that dramaticallyby providing, for the first time, a useful-ly dense grid of in situ data describingthe state of the entire modeled system.

The power of data assimilation has beendemonstrated convincingly by the nu-merical weather prediction models,which all use assimilation techniques.Employing these techniques in mag-netospheric modeling will result in adramatic breakthrough, since the dataassimilation will serve as an ultimatetest of the underlying model’s quality.Any systematic divergence of a modelfrom the data will provide a clue tosome intrinsic deficiency to be correct-

The flow field and mag-netic field generated bythe Lyon–Fedder–Mobarry MHD simula-tion, as measured by avirtual MagnetosphericConstellation mission.Gray vectors representthe local magnetic field,while colored vectors rep-resent the plasma flowfield with a time historyfrom each spacecraft dis-placed from the observingpoint according to theflow measurement. Thered trail of vectors clearlydelineates the channel-like flow burst duringthis period.

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Relevanceto Sun–EarthSystemsScience

Synoptic: adj.1. Of or related to dataobtained nearly simulta-neously over a large area.2. Manifesting or charac-terized by comprehen-siveness or breadth ofview.

ed. In addition, not only will the modelimprove overall, but also new knowl-edge will be gained about the physicalprocesses, whose incomplete or wrongdescription had caused the model tofail. In short, the data assimilation forces

THE MAGNETOSPHERIC CONSTELLATION

mission will establish a fundamen-tally new capability for the study ofconnections between the solar wind andEarth’s atmosphere and will make pos-sible the first synoptic studies of themagnetosphere, with impacts fullycomparable to the advent of station net-works for the study of troposphericweather. We can announce here the like-ly advances and contributions that willbe made using truly synoptic magneto-spheric data, but it must be admittedthat substantial surprises are almost in-evitable when so large a leap in capabil-ity is developed.

The elusive central goal of magneto-spheric physics has been to determinehow the magnetosphere stores, process-es, and releases energy in the magneto-tail, the role of important physical proc-esses therein, and how these processesinteract across all scales up through glo-bal. Earlier missions with lone or widelyspaced spacecraft have proved inconclu-sive with regard to this objective, just asobservations from individual weatherstations were inconclusive until a net-work of stations provided synoptic data.

MC will create a synoptic data base ofmagnetotail observations within whichmagnetospheric phenomena will be ful-ly depicted rather than debated. Havingthis, we will move on to debate thephysical processes that must be includ-ed in our simulations to capture thesephenomena and account for them. Wewill emerge from a long and frustratinghiatus during which the limitation ofspace missions to single station, orsmall groups of stations, crippledprogress on the understanding ofgeospace activity.

In addition, MC will be a trailblazingmission for other constellation missionsof the future. For example, an innermagnetosphere constellation and a he-liospheric constellation are under con-sideration as part of the most recentSun–Earth Connections Roadmap. MCand other constellations will be highlycomplementary to the missions of theLiving With a Star Program (LWS), par-ticularly the Radiation Belt StormProbes and the Heliospheric Sentinels.

a continuing reevaluation of our under-standing of how the magnetosphereworks. This is one of the primary driv-ers for the MC mission.

Contacts and More Information

Thomas.E.Moore@nasa.govhttp://sec.gsfc.nasa.govhttp://stp.gsfc.nasa.gov/missions/

mc/mc.htm

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Authors—

The STDT

ChairHarlan SpenceDepartment of Astronomy and Center for

Space PhysicsBoston UniversityBoston, MA

Project Study ScientistsThomas MooreLaboratory for Extraterrestrial PhysicsNASA Goddard Space Flight CenterGreenbelt, MD

Alex KlimasLaboratory for Extraterrestrial PhysicsNASA Goddard Space Flight CenterGreenbelt, MD

Committee Members

Brian AndersonApplied Physics LaboratoryJohns Hopkins UniversityLaurel, MD

Vassilis AngelopoulosSpace Sciences LaboratoryUniversity of California, BerkeleyBerkeley, CA

Wolfgang BaumjohannAustrian Academy of SciencesGraz, Austria

Joseph BorovskySpace and Atmospheric ScienceLos Alamos National LaboratoryLos Alamos, NM

Robert CarovillanoDepartment of PhysicsBoston CollegeChestnut Hill, MA

Paul CravenSpace Science DepartmentNASA Marshall Space Flight CenterHuntsville, AL

Joseph FennellSpace Particles and FieldsThe Aerospace CorporationEl Segundo, CA

Charles GoodrichCenter for Space PhysicsBoston UniversityBoston, MA

Michael HesseElectrodynamics BranchNASA Goddard Space Flight CenterGreenbelt, MD

Xinlin LiLaboratory for Atmospheric and Space PhysicsUniversity of Colorado, BoulderBoulder, CO

Kristina LynchDepartment of PhysicsDartmouth CollegeHanover, NH

Joachim RaederInstitute for Earth Oceans and SpaceUniversity of New HampshireDurham, NH

Geoffrey ReevesSpace and Atmospheric ScienceLos Alamos National LaboratoryLos Alamos, NM

David SibeckLaboratory for Extraterrestrial PhysicsNASA Goddard Space Flight CenterGreenbelt, MD

George SiscoeDepartment of Astronomy and Center for

Space PhysicsBoston UniversityBoston, MA

Nikolai TsyganenkoRaytheonNASA Goddard Space Flight CenterGreenbelt, MD

Project Formulation ManagerKenneth FordNASA Goddard Space Flight CenterGreenbelt, MD

Solar Terrestrial Probes Senior ProjectScientist

Richard VondrakNASA Goddard Space Flight CenterGreenbelt, MD

Solar Terrestrial Probes Senior Project Scientistfor Geospace

James SlavinNASA Goddard Space Flight CenterGreenbelt, MD

Solar Terrestrial Probes Program ScientistTodd HoeksemaNASA HeadquartersWashington, DC

Magnetospheric Constellation ProgramScientist

William K. PetersonNASA HeadquartersWashington, DC