A CREWED MARS EXPLORATION ARCHITECTURE USING FLYBY AND RETURN TRAJECTORIES

Andrew S.W. Thomas NASA Astronaut, Explora1on Branch, Astronaut Oce, NASA Johnson Space Center

Cesar A. Ocampo

Senior Engineer, Odyssey Space Research LLC., NASA Johnson Space Center

Damon F. Landau Jet Propulsion Laboratory, California Ins1tute of Technology

FISO Telecon 04-08-15

Presentation given by: C. Ocampo and D. Landau

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This presentation is not a stand-alone presentation document. It requires narration.

These are part of the results of an internal NASA-JSC study with NASA-JPL collaboration titled The Mars Lite Study

2015 All rights reserved

Inspira1on Mars Founda1on

Aims to launch a manned mission to y by Mars in by 2021

Founda1on claims that space explora+on provides a catalyst for growth, na+onal prosperity, knowledge and global leadership.

By taking advantage of this window of opportunity, the Inspira1on Mars Founda1on intends to revitalize interest in science, technology, engineering and mathema+cs (STEM) educa+on.

hPp://www.inspira1onmars.org/

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Figure Only: EME-Inspiration Mars Foundation. (in case next slide video does not work for some)

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Video: EME-Inspiration Mars Foundation. Click center of screen once to start.

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Figure Only: EME-Inspiration Mars Foundation Fly Around. (in case next slide video does not work for some)

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Video: EME-Inspiration Mars Foundation Fly Around. Click center of screen once to start.

Single Flyby Mission: fast in-and-out

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Ballistic single flyby Pass.

Speed up Catch up

dip in and out v v

v

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Figure Only: Single Flyby Mission: fast in-and-out: (in case next slide video does not work for some)

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Video: Single Flyby Mission: fast in-and-out: Click center of screen once to start.

Solu1on: Use Low Energy Flyby and Return Trajectories with Two Flyby Events

Inherit natural abort op1on

The two yby events separated by months

Place massive transit habitat(s) on these trajectories

eliminate inser_on and departure of massive assets into and out of Mars Orbit

1st yby event is used to drop o a crew taxi

2nd yby event picks-up and uses a hyperbolic rendezvous for Earth return

Assume Mars Stay Habitat has been Pre-deployed at Mars

Favor launch, en-route maneuvers, Earth arrival speeds over transit >mes. Assume no new major technology development.

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Work summarized and presented as paper AAS 15-372 at the 25th AAS/AIAA Space Flight Mechanics Mee1ng, Williamsburg, VA, January 2015

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Mars Free Returns

Damon Landau

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Broad Search of Mars Free-Returns Search parameters

Launch 20152052

Maximum ight 1me: 1200 days

Maximum Launch V: 7 km/s

Maximum Arrival V: 9 km/s

Minimum Mars yby al1tude: 300 km

Heliocentric revolu1ons between encounters: 0 or 1

Number of gravity assists: 1 or 2

Parameters specic to Star algorithm

Time step for encounter dates: 3 days

Maximum V at yby: 20 m/s

V step for 180 transfers: 20 m/s 13

Trajectory Search Methodology

1. Grid up Earth, Mars, and Earth encounter 1mes

2. Calculate outbound & inbound legs independently

3. Filter on low V to match in & out V at Mars

Turns a 3-D search into two 2-D searches

720M sequences considered with only 7.3M trajectory computa1ons (Lambert ts)

44,725 trajectories met all constraints

Flight time < 1200 d

Mars Flyby V < 20 m/s Alt > 300 km

Launch Dates

V < 7 km/s

Earth Return

V < 9 km/s 2015

2052

3-day increments

V constraint violated

Time node deleted

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Double-Flyby Free-Returns

Flight time < 1200 d

Launch Dates

V < 7 km/s

Mars or Venus

V < 20 m/s

Mars or Venus

V < 20 m/s

Earth Return

V < 9 km/s 2015

2052

3-day increments

EMME, EMVE, EVME sequences in single run

Transform 4-D search into three 2-D searches

280B sequences assessed with only 27M trajectory ts

1,425 trajectories met all constraints

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Building Mul1ple Flybys Flyby V calcula1on builds trajectory segments with three encounters:

departure body to yby body (incoming leg) and yby body to arrival body (outgoing leg).

The outgoing legs for one trajectory segment match with the incoming legs to another trajectory segment.

=

Launch Dates

Mars or Venus

Mars or Venus

Earth Return

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Launch Dates

Mars or Venus

Mars or Venus

Earth Return

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Flight Times

Trajectories in black also satisfy Trans-Mars Injection V < 4.5 km/s and Earth entry < 12.5 km/s

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Launch Opportuni1es

Trajectories in black also satisfy Trans-Mars Injection V < 4.5 km/s and Earth entry < 12.5 km/s

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3:2 Resonance Free Returns

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2:1 Resonance Free Returns

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Short Flight Time

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Double Mars Flyby

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Venus Flybys

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con1nue Using Free Returns for extended Human Mars Explora1on missions

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Determine how to use 2 yby events

Solu1on 1: Dual Habitat Concept

OTH = Outbound Transit Habitat RTH = Return Transit Habitat 26

Sketch credited to Ryan Whitley (JSC)

Solu1on 2: Loiter Habitat Concept

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Sketch credited to Ryan Whitley (JSC)

Copernicus: A Generalized

Trajectory Design and Op_miza_on System

Developed jointly between the University of Texas and the NASA Johnson Space Center (2001-present)

Hosted at NASA-JSC

Current Development at JSC

Current Lead Developer:

Jacob Williams, ERC-NASA-JSC, Houston, Texas

28 http://www.nasa.gov/centers/johnson/copernicus/

Used

Impulsive Gravity Assist to Real Flyby Conversion

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Impulsive Gravity Assist to Real Flyby Conversion

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Figure Only: Initial Guess for An Earth-Venus-Mars-Earth Free Return. Animation on next slide.

Earth Depart

Earth Arrive

Venus Flyby

Mars Flyby

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Video: EVME Trajectory Construction Iteration Sequence. Click center of screen once to start.

Dual Habitat Model

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Uses an Earth-Mars conjunc1on class trajectory for the Outbound Habitat and an Earth-Mars-Earth Flyby and Return Trajectory for the Return Habitat

Crew Taxi Drop-o and Transfer to a 1-Sol Orbit

1-Sol Orbit Departure and Hyperbolic

Rendezvous with Return Habitat

Low energy conjunc1on class Earth-Mars

3:2 Resonant Earth-Mars-Earth Free Return Trajectory (Habitat orbits Sun twice while the Earth orbits Sun 3 1mes

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OTHEarth Departure10/13/2039

RTHMars Flyby10/21/2041

OTHMars Arrival06/21/2040

RTHEarth Departure06/04/2039

RTH Earth Arrival05/13/2042

RTH E-M-E Trajectory

(3:2 Resonant w/Earth)

2039 2040 2041 2042 2043

RTH

OTH

EarthDep.

EarthDep.

MarsFly by

MarsFly by

Crew at Mars

EarthArr.

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Figure Only: Dual Habitat Model Animation on next slide

OTH Mars Arrive

RTH Mars Flyby Pickup, Hyperbolic Rendezvous

RTH Earth Arrive

RTH Earth Depart

OTH Earth Depart

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Video: Dual Habitat Model Animation. Click center of screen once to start.

Dual Habitat Model 37

Loiter Habitat Model Uses an Earth-Mars-Mars-Earth Flyby and Return Trajectory

Mars Flyby 1 to Mars Flyby 2

Loiter Leg

Crew Taxi Drop-o and Transfer to a 1-Sol Orbit

1-Sol Orbit Departure and Hyperbolic

Rendezvous with Loiter Habitat

In live discussion point out the key features/pros/cons

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Video: Loiter Hab Mars Centered Iteration Sequence. Click center of screen once to start.

41 Figure only: Converged Solution of previous slide video.

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Figure: Mars Arrival Flyby-Loiter-Mars Departure Flyby

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Figure only: Loiter Hab Mode;. (in case next slide video does not work for some)

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Video: Loiter Hab Model Animation. Click center of screen once to start.

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Figure Only: Loiter Hab Model Fly Around. (in case next slide video does not work for some)

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Video: Loiter Hab Model Fly Around. Click center of screen once to start.

Loiter Habitat Model Departure Earth

Mars Transit

Mars Mars Transit

Mars Earth Transit

Total MissionDuration

EarthDeparture

V

Mars Fly-by1V

Mars Fly-by2V

Earth ArrivalV

TotalEn-route

V

date day day day day km/s km/s km/s km/s km/s

6 Aug 2020 399 325 303 1028 3.794 2.550 3.018 4.714 1.676

8 Sep 2022 380 311 320 1010 3.673 2.573 2.887 3.787 0.621

05 Oct 2024 348 305 325 976 3.335 2.555 2.721 3.018 0.000

27 Nov 2026 280 303 358 941 4.000 2.942 2.989 3.546 0.126

29 Dec 2028 252 305 366 923 4.000 3.746 3.505 4.609 0.205

13 Feb 2031 223 321 379 924 4.000 3.804 3.251 4.317 0.515

31 Mar 2033 218 358 346 922 4.000 3.703 3.108 4.410 1.100

22 Jul 2035 364 346 213 923 4.000 3.100 3.737 3.884 0.856

10 Sep 2037 370 317 234 921 4.000 3.178 3.669 4.118 0.195

3 Oct 2039 367 305 267 939 3.530 2.852 3.041 4.045 0.000

21 Oct 2041 341 302 338 981 3.159 2.635 2.647 3.268 0.000

15 Oct 2043 331 303 381 1016 4.000 2.782 2.666 3.630 0.495

22 Jan 2046 244 315 375 934 4.000 3.762 3.289 4.227 0.477

13 Mar 2048 219 343 360 923 4.000 3.877 3.214 4.453 0.775

7 Jul 2050 347 361 209 917 4.000 3.046 3.606 3.721 1.068

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Drop-O from and Rendezvous with Transi_ng (Loiter) Habitat

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Drop-O from and Rendezvous with Transi_ng (Loiter) Habitat

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1st maneuver: capture, coast to apoapsis

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2nd maneuver: plane change, coast to periapsis

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3rd maneuver: capture into op1mal 1-Sol Orbit Mars Stay

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4th, 5th maneuver: depart and do Hyperbolic Rendezvous

Total In-and-Out DV cost = 2.308 km/s (Oct 2039) (this ranges from 2.1 to 3.1 for all 15 Loiter Habitat Solu_ons) 53

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Figure Only: Mars centered transfers, iteration sequence. (in case next slide video does not work for some)

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Video: Mars centered transfers, iteration sequence. Click center of screen once to start.

All Dual-Habitat, Loiter-Habitat Solu1ons require same type of Mars Centered Maneuvering

56 Note orienta_on of the 1-Sol Orbit

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Figure only: Capture-Departure Geometry Fly Around. (in case next slide video does not work for some)

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Video: Capture-Departure Geometry Fly Around. Click center of screen once to start.

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Figure only: Departure, Hyperbolic Rendezvous. (in case next slide video does not work for some)

Video: Departure, Hyperbolic Rendezvous. Click center of screen once to start.

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One chance to catch the train ride home.

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(image credit: The Darjeeling Limited, Fox Searchlight Pictures)

Solu_on 3: Hybrid Dual Loitering Habitat Model Four Flyby Events

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Six E-M-M-E Mission Possibili_es for the Hybrid Dual-Loitering Habitat Strategy

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Dual Loitering Habitat Model: Maneuver Data and Performance

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Concluding Remarks... ! Stair-step approach: Flyby-only, orbital, surface access,

access to Phobos, Deimos

! Launch vehicle (Space Launch System) requirements (ongoing work, paper TBP August 2015, Whitley et al.)

- Dual Habitat Model: Requires 3 SLS Block 2B Launches

- Loiter Habitat Model: Requires 2 SLS Block 2B Launches

! Inser1on-Departure to and from op1mal 1-Sol Orbit is feasible

! Pre-deployment of Mars Stay Assets yet to be addressed (ongoing)

! Sensi1vity studies of Hyperbolic Rendezvous wrt to delays, o-engine performance (ongoing work, paper TBP August 2015, Jedrey et al.) 67

Thank you

Thanks also to the other members of the NASA JSC-JPL Mars Lite Study Team

John Aitchison Lora Bailey Joe Caram Bret Drake Ricky Jedrey Kent Joosten Stan Love

Fay Mckinney Nathan Strange/JPL

Brenda Ward Ryan Whitley

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