Jet Propulsion Laboratory, California Institue of Technology The InterPlanetary Superhighway and the...

Jet Propulsion Laboratory, California Institue of Technology

The InterPlanetary Superhighway

and the Development of Space

ASI Futuristic Space Technologies 5/2002

Martin.Lo @ jpl.nasa.gov


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Trajectory Is a Key Space Technology

• Golden Age of Trajectory Technology Just Around Corner

• Trajectory Is a Mission-Enabling, Intellectual Technology– Not All Technology Is Hardware!

• Space H/W Technology and Trajectory MUST Develop Side by Side– Like “Rail Road Tracks” for the Train– Example: Ion Engines Have Been Around a Long Time, Their Use

Have Been Limited by the Lack of ‘Low Thrust’ Trajectory Design Tools


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Outline

• The InterPlanetary Superhighway (IPS)

• A New Paradigm for the Solar System

• Low Energy Orbits for Space Missions


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How It All Began: ISEE3/ICE

LOGO.049

Goddard Space Flight Center

GSFC: FARQUHARFARQUHAR, Dunham, Folta, et al

Courtesy of D. Folta, GSFC


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Current Libration Missions

• z

WIND SOHO ACE

GENESISMAP NGST

LOGO.049

Goddard Space Flight Center

Courtesy of D. Folta, GSFC


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Lagrange Points in Earth’s Neighborhood

• Every 3 Body System Has 5 Fixed Points Called Lagrange Points

– Earth-Moon-S/C: LL1, LL2, … LL5

– Sun-Earth-S/C: EL1, EL2, …

• They Generate the InterPlanetary Superhighway


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Orbital Zoology Near the Lagrange Points

• Four Families of Orbits, Conley [1968], McGehee [1969], Ref. Paper

• Periodic Orbit (Planar Lyapunov)

• Spiral Asymptotic Orbit (Stable Manifold Pictured)

• Transit Orbits (MUST PASS THRU LYAPUNOV ORBIT)

• Non-Transit Orbits (May Transit After Several Revolutions)

S: Sun Region

J: Jupiter Region

X: Exterior Region (Outside Jupiter’s Orbit)

X

S J


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[email protected] by Stable & Unstable Manifolds of

Unstable Libration Orbits

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• Unstable Periodic Orbits– Generate the Tubes

– Portals to the Tubes

• The Tubes Govern Transport– Transport Must Occur Thru Tubes

– Systematically Map Out Orbit Space

• Green Tube = Stable Manifold: Orbits Approach the L1 Periodic Orbit, No V Needed

• Red Tube = Unstable Manifold: Orbits Leave the L1 Periodic Orbit

Planet


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[email protected] Halo Orbit Transfer and Insertion Via


Genesis Mission: Uses LGenesis Mission: Uses L11, L, L22 Heteroclinic Heteroclinic Behavior to Collect & Return Solar Wind Behavior to Collect & Return Solar Wind

Samples to Earth Samples to Earth UTTR 84 x 30 km


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Nominal Trajectory NO Deterministic V!

13

8

1, 15, 16

23

46

7

9

11

14

-1

-0.5

0

0.5

1

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2

1 Launch 01/07/012 TCM-1 01/07/013 TCM-2 01/14/014 TCM-3 01/21/015 TCM-4 04/13/016 Halo Orbit Insertion (TCM-5) 04/23/017 Begin Science Phase 04/30/018 End Science Phase 03/22/039 Halo Orbit Departure (TCM-6) 04/01/0310 TCM-7 04/15/0311 TCM-8 06/10/0312 TCM-9 07/20/0313 TCM-10 08/09/0314 TCM-11 08/18/0315 Entry 08/19/0316 Backup Entry 09/07/03

ToSun

lunar orbit

haloorbit parking

orbit (option)

L+30d

Return

Transfer

Recovery

Science

14 11

976

43 2 1

8 13

-0.5

0.5

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2

14 11

97 6

43 21

813

-0.5

0

0.5

-1 -0.5 0 0.5 1

5

10

12

5

10

125

10

12

Y

Axis, in millions of kilometers:X = Sun-Earth Line, positive anti-sunY = (Z) x (X)Z = Ecliptic Normal

X

View from N. Ecliptic (Z-axis)

ToSun

Z

X

View from Anti-Earth Velocity (-Y-axis) View from Anti-Sun (X-axis)


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Genesis Mission Design Collaboration

Martin Lo JPL Genesis Mission Design Manager

Kathleen Howell Purdue University Department of Aeronautics and Astronautics

Brian Barden JPL, Purdue University

Roby Wilson JPL, Purdue University

Pioneer Work:

Numerical Exploration by Hand

JPL Lagrange Group

JPL Lagrange Group

Lunar Orbit

L1

L2

Halo OrbitPortal

Earth

New Paradigm:

Dynamical Systems Automation


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Why Dynamical Systems Theory?• Traditional Approach

– Requires First Hand Numerical Knowledge of Phase Space

– Each Trajectory Must Be Computed Manually (VERY SLOW)

– Cannot Perform Extensive Parametric Study or Montecarlo Simulation

– Optimization Difficult, Nearly Impossible

• Dynamical Systems Theory Provides – S/W Automatic Generation of Trajectories

– S/W Automatically Maps Out Phase Space Structures

– Near Optimum Trajectory

– Automatable Parametric Studies & Montecarlo Simulations

L1 L2

Halo Orbit

Earth

GenesisReturn

ISEE3/ICE Orbit Genesis Unstable Manifold


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[email protected] Reduced Genesis End-to-End Orbit Design

from 8-12 Weeks to 1 Day

Trade Parameters LTool Funding Level OptionsTotal Cost (Millions of Dollars) 0 1.72 M 2.3 M

Genesis Critical3.4 M

Multi-MissionCritical

Tool Cost0 1 M 2.3 M 3.4 M

Increase Funding to Genesis MissionDesign Workforce 0 0.72 M (4 WY) 0 0Genesis Operational Tool at JPL(% at JPL) 50% 75% 100% 100%Genesis Mission Design UpdateTurnaround Time 8-12 Weeks 1-2 Week 1 Day 1 DayGenesis Nominal Mission Design Work(% Planned Work Accomplished) 25% 100% 100% 100%Genesis Contingency Analysis Work Current Genesis Mission Design Budget Plan Includes Only Contingency Analysis for

Launch Error (< 3 Genesis Contingency AnalysisCapability Some < 3 < 3 > 3 > 3 Genesis Mission Design Risk

High Risk Medium Risk Low Risk Low RiskMultimission Support

None Very Limited Limited GeneralAdvanced Mission SupportInfrastructure None None None Yes

High Complexity: Tool use requires extensive training, process is time-consuming and error-prone.Low Complexity: Tool enables users to work at higher level, reduces time, error, and complexity.Very Limited: Provides infrastructure and tools adaptable for future missions with additional funding


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LTool Supported Genesis Launch Delay

• Genesis Launch Delayed from 2/01 to 8/01

• LTool Enabled Designers to Replan Genesis Mission in 1 Week

• Without LTool, Genesis Would Require Costly Additional Delay

• LTool and Dynamical Systems Contributed Significantly to Genesis’ Successful Launch on 8/8/2001.

L1 L2

Halo Orbit

Earth

GenesisReturn

ISEE3/ICE Orbit Genesis Unstable Manifold


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JPL LTool Team

Martin Lo Section 312 Task Manager

Dr. Larry Romans Section 335 Cognizant S/W Engineer (Marthematica Developer)

Dr. George Hockney Section 367 S/W Architecture & Sys Engineer

Dr. Brian Barden Section 312 Trajectory Design & Algorithms

Min-Kun Chung Section 312 Astrodynamics Tools

James Evans Section 368 Infrastructure S/W, Visualization Tools

Lunar Orbit

L1

L2

Halo OrbitPortal

Earth

InterPlanetary Superhighway: Many Different Types of Orbital Motions

JPL Lagrange Group

Earth Flyby & Capture

Genesis Earth Return Via L2

Hiten Lunar Capture

Lunar Flyby Escape to SIRTF Earth Trailer Orbits


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Tunneling Through Phase Space Via IPS

• Cross Section of Tube Intersection Partitions Global Behavior

– Yellow Region Tunnels Through from X Through J to S Regions

– Green Circle: J to S Region, Red Circle: X to J Region

– Genesis-Type Trajectory Between L2 and L1 Halo Orbits (Heteroclinic)


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Construction of Rapid Transition

• Manifold Intersections Computed Via Poincare Sections

• Reduce Dimension by 1, Tube Becomes Circle

• Intersections Provide Transit Orbits from L2 to L1


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Construction of Capture Orbits




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Construction of Heteroclinic Orbits



– Green Circle Leaves J to S Region

– Red Circle Enters J from X Region

• Intersections Provide Transit Orbits from L2 to L1


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[email protected] Chain

in Jupiter’s InterPlanetary Superhighway

• 2:3 to 3:2 Resonance Transport, No Energy Transfer Needed

• Source of Chaotic Motion in the Solar System

2:3 Resonance

Hilda 3:2 Resonance


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Genesis’ Homoclinic-Heteroclinic Chain

• Genesis Shadows Heteroclinic Cycle, Moon Plays Role (Bell et al.)

• SIRTF, SIM-Type Heliocentric Orbits Related to Homoclinic Orbits


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Theorem to Temporary Capture by Design

• The Existence of Homoclinic and Heteroclinic Cycles Implies We Can Choose An Infinite Sequence of Integers, Doubly Indexed,

N(i ,j) , i = Sun, L1, Jupiter, L2, Xsun; j = 1, 2, 3, …

N(i ,j) = Number of Revolutions Around Body(I), Called an ITINERARY

• THEOREM: There Exist an Orbit Which Realizes N(i ,j).

• Based on Conley-Moser’s Theorem on Symbolic Dynamics

• Voila! TEMPORARY CAPTURE BY DESIGN

Sun

N1

L1

N2

Jupiter

N3

L2

N4

XsunN5


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Orbit with Itinerary (X,J;S,J,X)

• Using Symbolic Dynamics Technique to Realize Complex Itinerary

• Capture Around Jupiter Multiple Revolutions (Specifiable)

• Note (2:3) to (3:2) Resonance Transition


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Foundation Dynamics Work

Wang Sang Koon Caltech

Martin Lo JPL, Principal Investigator

Jerrold Marsden Caltech Control and Dynamical Systems Department

Shane Ross Caltech


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[email protected] Paradigm of the Solar System

Copernican Model: Isolated Conic OrbitsNew Paradigm of the Solar System

InterPlanetary Superhighway Connects All


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IPS a New Pardigm of the Solar System

• InterPlanetary Superhighway Connects Entire Solar System

– Instead of Planets In Isolated Separate Conic Orbits

– Solar System Is An Organic and Integrated Whole Where Each Part Is Communicating with One Another

– Governs Transport and Morphology of Materials

• Shape Morphology of Rings and Belts

• Contributes to Theory of Motions of Comets, Asteroids, Dust

• Governs Planetary Impacts from Asteroids and Comets

– ShoemakerLevy9 Follwed Jupiter IPS to Final Impacts

– Genesis Trajectory Is an Impact Trajectory

– 1% of Near Earth Objects In Energy Regime of Genesis Trajectory, Considered Most Danerous

• This Theory Contributes to Understanding of our Origins


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Examples from Nature: Comet Oterma

• Theme: Use Natural Dynamics to Optimize V for Space Missions:

– Genesis 6 m/s Det. V

• Jupiter Family Comets

• (2:3) to (3:2) Free Resonance Transition

• Temporary Capture

• L1, L2 as Gate Keeper

• What Is Source of Chaotic Dynamics?


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L1, L2 Manifolds and Comet Orbits

• L1, L2 Manifolds Have (2:3) to (3:2) Resonance Transitions

• Manifolds Match Oterma’s Orbit Well

• Also Matches Gehrels3 Orbits

– Temporary Capture

– Near Halo Orbit

• L1, L2 Manifolds Are DNA of This Dynamics

• Need to Study Invariant Manifold Sturcture


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[email protected] Oterma Shadows

Jupiter’s Heteroclinic-Homoclinic Cycles


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[email protected] the Orbit Space

Using Poincare Sections

.

.Orbits

..Poincare Map

.


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Poincare Section of Jupiter’s IPS

3:2

Hilda Asteroid Group

4AU

2:1

Kirkwood Gap

2.1 AU


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Asteroid Belt Stucture Induced by IPS

• Poincare Section from Single Orbit Leaving Jupiter L1

– Each Dot Is a Rev Around the Sun

– Spirals Towards Inner Solar System

– Eccentricity Grows

• Indistiguishable from Ordinary Conic Orbits

• Controls Asteroid Belt Structures

• Controls Dust Transport and Morphology

• Intimate Connection with Low Thrust Trajectory Design

Semi-Major Axis

Ecc

entr

icit

yA

rg P

erih

elin

3:2 Stable

2:1 Mars Crosser

ECC = .5

ECC = .05

2.1 AU 4 AU


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IPS ExoZodi Dust Signatures for Planet Detection

• Earth’s Zodi Dust Ring Simulated WIth Lagrange Point Dynamics– Only Gravity, No PR Drag

• S: Sun Region, Earth: Planet Region, X: Exterior Region

• May Provide Planetary Signatures for Exo-Planet Detection

S

EARTH

X


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IPS and Transport in the Solar System

Legend

L1 IPS Orbits

L2 IPS Orbits

Comets

Asteroids

Kuiper Belt

Object

Poincare Section of the InterPlanetary Superhighway


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Discovery of InterPlanetary Superhighway

Martin Lo JPL Genesis Mission Design Manager

Shane Ross Caltech Control and Dynamical Systems


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Around the Solar System in 80K Days

• FREE Spiral Orbit Transfer of KBO to Asteroid Belt Produced by LTool Using IPS

– Origin of Jupiter Comets

– Replenish Asteroid Belt

– Escape from Solar System

• Less Than 1 Pluto Year

• Scales for Jupiter and Saturn Satellite Systems

• Suggests New Low Thrust Algorithm

Jupiter

Saturn

~Uranus (fictitious mass)

~Neptune (fictitious mass)

Kuiper Belt Object (KBO)


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From AU to au: Comets & Atomic Physics

Atomic L1

Comet’s Potential Energy Surface

Comet L1 , L2

• Uncanny Similarity of Transport Theory in 3 Body Problem

• Rydberg Atom In Cross Fields

• Chemical Transition State Theory

• Jupiter

• Nucleus

• Jupiter

Atomic Halo Orbit

Atomic Potential Energy Surface


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Mars Meteorite

• Build Instruments & S/C Lunar L1 Station

• Transfer S/C from L1 to Earth-L2 LIO (Libration Oribit)

• Service S/C at Earth L2 LIO from Lunar L1 Gateway Hub


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Asteroid Transport Rate Near Mars*

Charles Jaffe West Virgina University

Shane Ross Caltech

David Farelly Utah State University

Martin Lo JPL

Jerrold Marsden Caltech

Turgay Uzer Georgia Tech

* To appear in “Physical Review Letters” (7/1/02)


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SL9 Impact Via Jovian IPS


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River of Life: Astrobiology


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1% Near Earth Objects Have IPS Energies

Armageddon Or Opportunity?


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IPS and Development of Life: Exobiology

• InterPlanetary Superhighway Brought Life Building Material from Comets and Asteroids to Earth

• InetrPlanetary Superhighway May Have Brought the Asteroid Killing the Dinosaurs Via a Genesis-Like Orbit

– Presence of Abundant Iridium Implies Slow Impact Velocity

– Conjectured by Mike Mueller et al (Nemesis Star)

• InterPlnaetary Superhighway Theory Can Provide Critical Transport Rates for Astrobiology

– How Rates Determine Formation of Life on a Planet

– Can Rates Be Obtained from ExoZodi Signatures to Find Potential Life Bearing ExoPlanets?


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RESCUE MISSION 911:

Hiten, HAC

Discover, June 1999


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Dynamics of Hiten Lunar Capture Orbits


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Designing a Lunar Capture Orbit

TRAJECTORIES FROM SUN-EARTH EXTERIOR

REGION

TRAJECTORIES FROM SUN-EARTH

INTERIORREGION

TO EARTH-MOON INTERIOR REGION

CONTAINS ALL EARTH TO LUNAR CAPTURE ORBITS ON ENERGY SUFACE

A CROSS SECTION OF THE SUN-EARTH AND EARTH-MOON IPS PARTITIONS THE ORBITAL DESIGN SPACE INTO CLASSES


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Construction of Capture Orbits



Moon


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Shoot the Moon

Shadowing Unstable Manifold of Earth L2 Lyapunov Orbit

Shadowing Stable Manifold of Earth L2 Lyapunov Orbit to Leave Earth

Earth

Lunar Orbit

36 m/s Maneuver to Transfer to Stable Manifold of Moon L2 Lyapunov Orbit

Ballistic Lunar Capture

Hiten-Like Low Energy Transfer & Ballistic Lunar Capture

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Shoot the Moon


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Shoot the Moon: Lunar Capture




Shane Ross Caltech


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TPF in Formation Flight Near L2

TPF Formation

L2To Sun & Earth


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TPF in SIRTF/SIM-Like Heliocentric Orbit

TPF Formation


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First Formation Flight Design Around L2

For the Terrestrial Planet Finder Mission (TPF)

Min Kun Chung JPL

Gerard Gomez Barcelona University

Martin Lo JPL, TPF Mission Design Lead

Josep Masdemont Polytechnic University of Catalunya

Ken Museth Caltech Computer Graphics Group

Larry Romans JPL


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[email protected]: Human Service to Libration Missions

• ISSUE: 3 Months Transfers to EL2 Too Long for Humans

• Short Transfers Too Difficult

• Infrastructure Too Expensive

STA-103 astronauts replaced gyros needed for orientation of the Hubble Space Telescope.

JSC

TPF @Earth L2


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[email protected]: Human Servicing at Lunar L1 Gatewy

• Build Instruments & S/C Lunar L1 Gateway for EL2

• Service S/C at Earth L2 from Lunar L1 Gateway Module

EARTH

EARTH L2 HALO ORBIT

MOON

LUNAR L1 HALO ORBIT

LUNAR L2 HALO ORBIT

LUNAR L1 GATEWAY


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Lunar L1 to Earth L2 Transfer

• Build Instruments & S/C Lunar L1 Station

• Transfer S/C from L1 to Earth-L2 LIO (Libration Oribit)

• Service S/C at Earth L2 LIO from Lunar L1 Gateway Hub

L1

Lunar L2

Earth

L2

Lunar Rotating Frame Earth Rotating Frame

Lunar


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Lunar L1 Gateway Human Servicing

Mission Concept Development and Design


Initial Trajectory Design (2D, Coupled RTBP Model)

Shane Ross Caltech

Detailed Trajectory Design (3D, Full Ephemeris Model)

Min Kun Chung JPL

Animation

Cici Koenig Caltech Graphics Group

Alan Barr Caltech Graphics Group


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Transport Between the Jovian Moons

• Cross Section of Manifolds Plotted in {a, e} Elements

• L1 Manifold of Europa Intersects L2 Manifold of Ganymede, etc.

• Provide Transport Between Moons

• May Require V

– Much Lower than Hohmann

Transport Between Jovian Moons


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Petit Grand Tour of Jovian Moons

Mission Concept Flexible Itinerary, Visit Jovian Moons in Any Order

User Low Energy Transfer, Capture, Impact

Near Circular Orbits Reduce Jupiter Radiation

Proof of Concept Point Design Using the Interplanetary Superhighway 25 Day Transfer from Ganymede to Europa

Requires DV of 1452 m/s!

Compare to Hohmann Transfer of 2822 m/s!

Free Capture by Europa for 4 Orbits (More Possible) Tour Also Available for Saturn’s Moons

Applicable to Europa/Titan Orbiter, Lander, & Other Outer Planets Missions


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New Frontier: Petit Grand Tour?

• New Computation by Shane Ross

• Serial Visits to Galilean Moons, Final Europa Capture

• Total V ~ 20 m/s! 1500 Days Time of Flight


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Petit Grand Tour




Shane Ross Caltech


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• To Design Low Thrust Orbits, You Must Understand IPS

• Computed from Single Orbit Leaving Europa L2

– Each Dot Is a Rev Around Jupiter

– Spirals Towards Europa

– Eccentricity Grows

• Full of Useful Unstable Orbits

– Similar to L1/L2 Halo’s

– More Tubes!

• Indistiguishable from Conic Orbits

• New Low Thrust Trajectory Design

– Use This Transition as First Guess

New Approach to Low Thrust Orbits

Europa’s IPS


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Low Thrust Orbit Naturally Uses IPS!

• Low Thrust Transfer to Mars Via Lunar L1 to L2 Transfer

• Courtesy of G. Whiffen Computed by MYSTIC


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Low Thrust to Lunar Gateway L1 Halo Orbit

• Low Thrust Trajectory Courtesy of G. Whiffen, Computed by MYSTIC

• Halo Orbit Computed by LTool


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IPS Technology Road Map

Three Steps: Discover, Understand, Apply

• Map the InterPlanetary Superhighway– First Step in Discovery and Exploration– Like “Human GENOME”, “Star Catalogs”, Rand McNally Maps

• Integrate Orbital Dynamics Theories– IPS Orbits– Continuous Thrust Orbits– Conics Orbits

• Develop New Mission Concepts


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References

• Barden, Howell, Formation Flying in the Vicinity of Libration Point Orbits, AAS 98-169, Monterey, CA, 2/98

• Barden, Howell, Dynamical Issues Associated with Relative Configurations of Multiple Spacecraft Near the Sun-Earth/Moon L1 Point, AAS 99-450, Girdwood, Alaska, 8/99

• Gomez, Masdemon, Simo, Lissajous Orbits Around Halo Orbits, AAS 97-106, Huntsville, Alabama, 2/97

• Howell, Barden, Lo, Applications of Dynamical Systems Theory to Trajectory Design for a Libration Point Mission, JAS 45(2), April 1997, 161-178

• Howell, Marchand, Lo, The Temporary Capture of Short-Period Jupiter Family Comets from the Perspective of Dynamical Systems, AAS 00-155, Clearwater, FL, 1/2000

• Koon, Lo, Marsden, Ross, Heteroclinic Connections between Lyapunov Orbits and Resonance Transitions in Celestial Mechanics, to appear in Chaos


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References

• Koon, Lo, Marsden, Ross, The Genesis Trajectory and Heteroclinic Connections, AAS99-451, Girdwood, Alaska, August, 1999

• Koon, Lo, Marsden, Ross, Shoot the Moon, AAS00-166, Clearwater, Florida, January, 2000

• Lo, The InterPlanetary Superhighway and the Origins Program, IEEE Aerospace2002 Conference, Big Sky, MT, February, 2002

• Lo et al., Genesis Mission Design, AIAA 98-4468, Boston, MA, August, 1998

• Serban, Koon, Lo, Marsden, Petzold, Ross, Wilson, Halo Orbit Correction Maneuvers Using Optimal Control, submitted to Automatica, April, 2000

• Scheeres, Vinh, Dynamis and Control of Relative Motion in an Unstable Orbit, AIAA Paper 2000-4135, August, 2000

Jet Propulsion Laboratory, California Institue of Technology The InterPlanetary Superhighway and the...

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