A long time ago in a NASA far,
far away….
(
)
Noam R. Izenberg, Ralph L. McNutt
JHUAPL, Laurel, MD, USA
International Venus Conference 2016
Oxford UK 4-8 April, 2016
Age of EMPIRE: Origins
•  1956 paper by Gaetano Crocco, 7th Int’; Astronautical Foundation
Congress in Rome. Earth-Mars-Venus-Earth flyby mission to save fuel.
•  Beginning of over 2 decades of human spaceflight studies looking
beyond the moon.
•  EMPIRE - Early Manned Planetary-Interplanetary Roundtrip
Expeditions
•  Human space flight was assumed in an age before capable
robotic craft.
Age of EMPIRE: 60’s – 70’s
(Drake
& Watts
Eds DRA
Appdx2
2014, &
others)
Opposition vs. Conjunction class missions: Short vs. long stay
•  AEC-NASA nuclear rocket program,
established in 1960; Nova rocket
program.
•  Explore advanced operational
concepts necessary for flyby and
orbiter missions.
•  Other studies leveraged Apollo
instead.
(Time/Life)
Age of EMPIRE: 60’s – 70’s
(Drake
& Watts
Eds DRA
Appdx2
2014, &
others)
Opposition vs. Conjunction class missions: Short vs. long stay
Aerojet-General Coorp – Westinghouse
Astronuclear Laboratory
Aeronutronic Division of Ford Motor
Company
General Dynamics/Astronautics
Lockheed Missiles and Space Co.
Belcomm Inc.
Univelt Inc.
(Time/Life)
Age of EMPIRE: 60’s – 70’s
Planetary JAG Phase 1, 1966
•  ‘Feasible’ Piloted Mars/Venus Flybys (1975-80)
–  Piloted Mars flyby leave Earth-orbit in Sept 1975.
–  Mars flyby launch opportunities in Oct 1977 and Nov 1979.
–  Multiple flyby missions were possible
•  Venus/Mars mission Dec 1978,
•  Venus/Mars/ Venus mission Feb1977.
•  Dispense automated probes based on Mariner and Voyager
technology.
•  Piloted Mars Landing and piloted Venus Capture (orbiter)
missions (post-1980) would see introduction of AEC-NASA
nuclear-thermal rockets.
•  EMPIRE study mandate assumed nuclear propulsion was
coming, and Planetary JAG deemed nuclear propulsion
“essential for a flexible Mars landing program” capable
of reaching Mars in any launch opportunity regardless of
the energy required.
Age of EMPIRE: 60’s – 70’s
•  Piloted Venus Flybys
•  Triple Planet Flybys (with abort option)
•  Multiple planet flybys to Venus and Mars.
•  Piloted Venus Orbting Mission (1967)
•  Buoyant Venus station (1972-1973 launch)
(1969)
•  Nuclear rocket programs did not survive
the 60’s
–  Final NERVA cancellation 1972)
Fallen EMPIRE: 80’s – 90’s
•  Nuclear rocket programs long gone.
•  End of Apollo was also the end of
Apollo derivative human spaceflight.
•  Focus of Planetary missions on
increasingly capable robotic craft.
•  Refocus of human spaceflight to LEO,
Shuttle, ISS
–  Interplanetary Mission Design Handbook
(George & Kos 1998): No DRM
opportunities that includs Venus.
•  Reduction, loss of US human rated
heavy lift.
Ashes of EMPIRE:
st
21
Century
•  Human spaceflight targets: Mars, Moon,
Asteroids…Venus?
–  Venus competitive with MB Asteroids (Landis,
2003)
•  Human spaceflight focus on pathway to Mars
•  Heavy planetary payloads as part of revived
heavy lift capability (SLS)
•  Venus scenarios remain in Design Reference
Architecture (DRA, 2009, through latest
addendum (#2) 2014)
–  But not focused upon
–  Opportunity unexplored / unexploited
Ashes of EMPIRE:
st
21
Century
(Drake & Watts Eds, DRA Appdx2 2014)
Ashes of EMPIRE:
•  Opposition flight
opportunities where
both Total ΔV and Total
Mission Duration are
low.
•  From near “double
flyby” to Mars Mission
Durations up to 100
days.
•  Multiple arguments for
Piloted Venus flybys
st
21
Century
Venus to Mars: Mars via Venus
•  Venus as possible essential waypoint
to human Mars exploration.
•  Mars via Venus
–  Reducing ΔV cost
–  Shortest total mission duration for Mars
stay and reasonable ΔV
•  Possibly crucial for early exploratory missions
–  Variety of Opposition Class missions to
Mars
Venus to Mars: Venus flyby
Precursor
•  Mission opportunity
cadence
–  Venus: 19 mo / <8
years
–  Mars: 26 mo / 15-18
years
•  Mission Time: Missions
~ 1 year.
•  Delta V Lower still
Earth-Venus-Earth (EVE) mission
(Crain et al., 2000)
Venus to Mars: Human Factors
•  Time: Shorter duration vs crew stress
•  Power: plentiful. EVE more easily/
conventionally powered for long
mission
•  Thermal protection
•  Radiation exposure
Radiation Hazards
Mission radius
vs
Mission day
(2006 and 2010 model missions)
•  Radiation Limits EVE vs
EME
–  30 day max doses less for
EVE
–  Total doses comparable
for both
Mission radiation
vs
Mission day
•  Solar Cycle and Solar
distance:
–  More active sun reduces
Cosmic Ray risk, greater
reduction closer to sun
Crain et al., 2001
Radiation Hazards
•  Increased CME/
SPE risk
–  more mitigateable than CR
–  Mitigation (e.g.
‘storm cellars’)
Necessary for all
interplanetary
targets
regardless
(French, 1967)
Energy spectra of nucleons and electrons in
interplanetary space near Earth orbit. Flares
also shown.
Miroshnischenko, 2003, Lin, 1980
The Case for,
and Opportunity of Venus
•  Multiple arguments for human
spaceflight to include Venus as flyby
destination alone and/or on way to
Mars.
•  Significant opportunity for Venus
planetary community (science)
•  Significant opportunity for diverse
NASA communities (e.g. HEOMD,
SMD)to advocate for common goal.
A New EMPIRE
•  Large Probes Enabled by SLS carrying
capacity
–  Power, Data volume, Capability
–  SLS leverage-able without piloted flyby.
•  Real-Time Telemetry
–  No light speed delay
–  Tele-operated probes
–  Human decision making in the loop
•  Guided aerial and landers (flight/descent control)
•  Optimized sampling
•  Sample Return (Upper atmosphere)
•  Beyond (HAVOC)
…Or the rise of VAMPIRE
•  Bringing a version of EMPIRE back from the
dead as Venus And Mars Piloted
Interplanetary Roundtrip Expeditions
•  Requires revival of certain ambitions and ways
of thinking, with application of current tech
•  Requires new generation to be aware of the
work that has been done before
•  Requires advocates in Path to Mars and
planetary community.
“Humans to Mars Via Venus” is logical, smart,
and should be the path we take.
And with that comes unprecedented
opportunity for Venus science.
References 1
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Crocco, Gaetano A. “One-Year Exploration-Trip Earth-Mars-Venus-Earth,”
Rendiconti del VII Congresso Internanzionale Astronautico, Associazione Italiana
Razzi, 1956, presented at the Seventh Congress of the International Astronautical
Federation, Rome, Italy, 1956, pp. 227-52.
Harry Ruppe, Manned Planetary Reconnaissance Mission Study: Venus/Mars Flyby
(Huntsville, AL: NASA/TM X-53205, 1965).
Gillespie, R.W., and Ross, S. "Venus-swingby mission mode and its role in the manned
exploration of Mars." Journal of Spacecraft and Rockets 4, no. 2 (1967): 170-175.
Feldman, M. S. et al. "Manned Venus Flyby." Belcomm, Inc., TR-67-600-1-1,
Performed for NASA Manned Space Flight Center under Contract NASw-417 (1967).
Gray, Edward, and Franklin Dixon. “Manned Expeditions to Mars and Venus,” Eric
Burgess, editor, Voyage to the Planets. San Diego: Univelt, Inc., 1967, pp. 107-35.
Spacecraft Engineering Branch, Apollo-based Venus/Mars Flybys (Houston: NASA
MSC, September 1967).
Contracting Officer to Prospective Contractors, “Planetary Surface Sample Return
Probe Study for Manned Mars/Venus Reconnaissance/Retrieval Missions,” Request
for Proposal No. BG721-28-7-528P, 3 August 1967.
Ordway, F. I. III et al. “EMPIRE: Early Manned Planetary-Interplanetary Roundtrip
Expeditions Part I: Aeronutronic and General Dynamics Studies.” J. Brit. Interplanet.
Soc. 46 (1993): 179-190
Ordway, F. I. III et al. “EMPIRE: Early Manned Planetary-Interplanetary Roundtrip
Expeditions Part II: Lockheed Missiles and Space Studies.” J. Brit. Interplanet. Soc. 47
(1994): 181-190
References 2
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Dewar, J. A. “Atomic Energy: The Rosetta Stone of Space Flight.” J. Brit. Interplanet.
Soc. 47 (1994): 199-206
George, L.E. and Kos, L. D. “Interplanetary Mission Design Handbook:
Earth-to-Mars Mission Opportunities and Mars-to-Earth Return Opportunities 2009–
2024.” NASA TM-1998-208533 (1998), 162 pp.
Crain, T. et al. "Interplanetary flyby mission optimization using a hybrid global-local
search method." Journal of Spacecraft and Rockets 37, no. 4 (2000): 468-474.
Crain, T. et al. "Radiation Exposure Comparison of Venus and Mars Flyby
Trajectories." Journal of Spacecraft and Rockets 38, no. 2 (2001): 289-291.
Landis, G.A. "Colonization of Venus." Expanding the Frontiers of Space 654 (2003):
1193-1198.
Portree D.S.F. Humans to Mars, Fifty Years of Mission Planning, 1950-2000, NASA
SP-2001-4521, 2001, 151 pp.
McNutt R.L. et al. “Propulsion for Manned Mars Missions: Roundtable 3” 10-IWCP
Lafleur, J.M., and Saleh, J.H. "Survey of intra-and inter-mission flexibility in space
exploration systems." Acta Astronautica 67, no. 1 (2010): 97-107.
Foster, C. and Daniels, M. “Mission Opportunities for Human Exploration of Nearby
Planetary Bodies.” AIAA Space 2010 Conf. & Expo. 30-Aug-2-Sept, 2010. AIAA
2010-8609.
Design Reference Architecture (DRA) for Mars:
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DRA Mars 5.0: Drake B.G., Ed. “Human Exploration of Mars Design Reference Architecture
5.0.” NASA/SP-2009-566 2009, 100 pp.
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Summary paper – same title IEEEAC paper #1205 does not mention Venus.
DRA Addendum #1, Drake B.G., Ed., NASA/SP-2009-566-ADD, 2009, 406 pp.
DRA Addendum #2, Drake B.G. and Watts, K.D., Eds., NASA/SP-2009-566-ADD, 2014, 598 pp.