Asteroid Retrieval Technology
Development
From the
Asteroid Return Mission Study
Technical Development
Start: 1 Dec 2012
Technical Development End: November 24, 2017
Final Technical Report Submission: 4 May 2018
Team Leads:
Paul Dimotakis and Thomas Prince
California Institute of Technology
pxd@tyrvos.caltech.edu and prince@caltech.edu
John Brophy
Jet Propulsion Laboratory
John.r.brophy@jpl.nasa.gov
Louis Friedman
Planetary Society (Emeritus)
louisdfriedman@gmail.com
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I. List of Participants
Caltech Campus:
Prof. Fred Culick
(Engineering and Applied Science)
Prof. Paul Dimotakis
(Engineering and Applied Science)
Prof. William Goddard
(Chemistry and Chemical Engineering)
Dr. George Helou
(Infrared Processing and Analysis Center, Physics, Math
and Astronomy)
Dr. Andres Jaramillo-Botero
(Chemistry and Chemical Engineering)
Prof. Shri Kulkarni
(Physics, Math and Astronomy)
Dr. Russ Laher
(Infrared Processing and Analysis Center, Physics, Math and
Astronomy)
Dr. Frank Masci
(Infrared Processing and Analysis Center, Physics, Math
and Astronomy)
Prof. Thomas Prince
(Physics, Math and Astronomy)
Graduate student: Adam Waszczak
(Physics, Math and Astronomy)
JPL:
Dr. John Brophy
Dr. Brian Bue
Dr. B. Gershman
Dr. Umaa Rebbapragada
Dr. Nathan Strange
External:
Dr. Louis Friedman, The Plan
etary Society (Emeritus)
Dr. Marco Tantardini,
The Planetary Society
II. Executive Summary
Goal of program
The Keck Institute for Space St
udies (KISS) workshops on the
Asteroid Return Mission concep
t explored and established the
feasibility of capturi
ng and returning an entire near-Earth asteroid
(NEA) to lunar orbit by the middle
of the next decade, and identified
the benefits that such an endeavor would provide to NASA, the
nation, and the world.
The goal of this technology development
program was to start the process of
working select technical issues
identified in the study
to significantly enhan
ce the prospects of
making the asteroid capture and return mission a reality.
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Key areas of accomplishment
Mission architecture definition
1. Trajectory design
2. SEP propulsion technology
3. Mission/System Design
4. Solar Thermal Power & Propulsion Technology Introduction
a. Study beam-forming deploy
able reflector designs for
solar concentrators.
b. Monitor progress in solar-electric power production
technologies.
Small Near Earth Asteroid (NEA) detection
1. Modifications to the search
/detection software employed in
the Palomar Transient
Factory (PTF).
2. Demonstration of the upgra
ded PTF as a useful tool for
detecting small NEAs.
In-Situ Resource Utilization (ISRU)
for asteroids, specifically for
power and propulsion
Initial KISS study
Two successful KISS workshops were
convened on this subject (Sept 27-
30, 2011 and Feb 7-8,
2012), and additional su
pporting work was
performed outside the workshops. A st
udy report was delivered to KISS
in April 2012 (http://kiss.caltech.edu/pr
ograms.html#asteroid). This report
documents the challenges and opportuni
ties arising from capturing,
characterizing, and mining a small (7-m
diameter) NEA. The results of the
initial study are also described in A
ppendix A of this report. The technical
development effort selected four ar
eas from among a number of technical
challenges identified
in the study. These
are mentioned above.
Technical Development Wor
kshop (April 7-9 2014)
Applications of Asteroid Redire
ction Technology. (35+ attendees)
Workshop description:
“Since the development of the asteroid retrieval mission concept a
number of suggestions and ideas
have been brought forward for
applications to other missions (with in
terplanetary destinat
ions), planetary
defense, human space transportation, commercial exploitation and
science investigations. We believe cons
ideration of other applications is
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important, in part to increase underst
anding the multiple
potential benefits
of asteroid retrieval and in
part to offset concerns that the technology is a
"one-off," applicable to a single missi
on and not part of the NASA future.
The asteroid retrieval mission concept
is envisioned as a supporting step
in the long-range human
exploration program
for missions beyond the
Moon and eventually to Mars. Broader c
onsideration of the technologies
and opportunities inherent with asteroid retrieval would help put the first
proposed asteroid retrieval mission in
context as an essential step in
expanding human presence bey
ond low Earth orbit.”
III. Outcomes of the tec
hnical development program
The ARM mission studies had very signif
icant impact on NASA, resulting in a
large amount of funding being alloca
ted to develop and implement an ARM
mission. However, with a change in US
administration, the mission was
cancelled in 2017 (
spacenews.com/nasa-closing-out-a
steroid-redirect-mission/).
There were numerous results from this
technical development
program. Here
we report on the two areas which produced t
he most significant results: mission
architecture and detection of small NEAs.
Mission Architecture Studies
Mission Architecture
:
The Mission Architecture task wa
s completed and documented with the
publication of Synergies of Robotic As
teroid Redirection Technologies and
Human Space Exploration
1
at the 65th Conference of the International
Astronautical Congress (2014). Wher
eas the first year of technical
development for the Asteroid Retrieva
l study focused on the feasibility and
mission design for capturing and moving a sma
ll asteroid from its natural orbit to
cis-lunar space, the later technology
development task examined how the
various technologies required for such a
mission can be used in other planetary
exploration applications and might be incor
porated in an architec
ture to extend
human exploration to Mars. A workshop wa
s held in April 20
14 on Applications
of Asteroid Redirection Technology,
attended by 35+ participants.
1
IAC-14.A5.3-B3.6.7, x26388: John R. Brophy, Jet
Propulsion Laboratory, Caltech; Louis Friedman,
Executive Director Emeritus, The Planetary So
ciety ;Nathan J. Strange, Jet Propulsion Laboratory,
Caltech; Thomas A. Prince. Director, Keck Inst
itute for Space Studies, Caltech; Damon Landau, Jet
Propulsion Laboratory, Caltech; Thomas Jones, Fl
orida Institute for Human and Machine Cognition;
Russell Schweickart, B612 Foundation; Chris Lewicki,
Planetary Resources, Inc.;
Martin Elvis, Harvard-
Smithsonian Center for Astrophysics; David
Manzella ,NASA Glenn Research Center, USA
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This workshop and the original study
report formed the basis of the IAC
publication mentioned above. The areas of
research and technology included
solar electric propulsion use on cargo mi
ssions to support human space flight,
analysis of resonant heliocentric orbits
that might enable intermediate flights
between Earth and Mars, planetary defense appl
ications of asteroid deflection,
and applications to utilizati
on of putative asteroid resources. A single
architecture could, in prin
ciple, be derived fr
om the options st
udied, but that
would of course depend
on program objectives
outside the scope of a
technology development study. Instead, va
rious pathways for applications were
identified, as well
as areas for further study. A summary chart of all the
considerations appears above.
The legacy of the ARM program
is described in Appendix B.
Solar-thermal propulsion:
Part of the Mission Architecture effo
rt was to develop solar-thermal power
technology for multiple uses. One use is to take advantage of the anticipated
availability of large
quantities of water in cislunar
space enabled by the return of
one or more C-type asteroids. A 500-
t, carbonaceous C-type asteroid may
contain up to 100 t of water. This water,
once extracted from the asteroid, could
be used both for radiation shielding to
protect astronaut crews from galactic
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cosmic rays or in a solar-thermal propulsi
on system to provide transportation to
a radiation-shielded
habitat. Initial solar-thermal
systems would likely use water
directly as the propellant. Longer-term sys
tems could use hydrogen (obtained by
the electrolysis of water from the astero
id) to provide better performance. This
has the potential to revolu
tionize human space transpor
tation in a bootstrapping
manner. Further, solar-thermal power could
be used directly, i.
e., without paying
a Carnot-efficiency factor penalty, in
the form of concentrated solar beams
formed by suitable optics, with concentra
tion factors in t
he range of 30-100,
yielding fluences at 1 AU in the range
of 65-130 kWsol/m2. This power could be
used to facilitate water extraction, but
also to enable mining operations. Solar
electric propulsion is used to retrieve t
he first few asteroids, and then after the
capability is established to extract lar
ge quantities of water from these objects,
solar thermal propulsion – if it can be su
ccessfully developed – would take over
and be used to transport astr
onaut crews in deep space.
As part of the solar-thermal effort, a
1 m diameter proof-of-concept physical
model of a cylindrical gore solar concent
rator was built. The model was made of
50 m thick Kapton and it was supported
by a rigid Aluminum edge frame. The
surface gores were precision cut using
templates made with a laser cutter. The
rib panels were cut using paper templates.
A lightweight design for the central
hub was developed. The proof-of-concept
model is shown in the following
Figure.
Front view of proof-of-concept model
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Small NEA Detection
- Advances in Techniques to Search for Small
Asteroids
As part of the Keck program that initia
ted the NASA Asteroid Return Mission
(ARM), technical development work was
undertaken with KISS funds to develop
new techniques for detecting small asteroids, down to 5-10 meters in size,
appropriate as possible c
andidate targets
for the ARM mission. Work was
initiated using the Palomar Schmidt
Telescope using a CCD camera with 7.25
square degree field of view and making
60-second exposures. Small asteroids
can only be detected close to the Earth
because of the small amount of light
they reflect and therefore they have la
rge angular velocities across the sky,
somewhat analogous to earth satellites.
They therefore ap
pear as linear
features (“streaks”) in the im
ages from the Schmidt telescope.
A sophisticated software pipeline was devel
oped to identify asteroid streaks
employing machine-learni
ng techniques (see Waszczak et al., reference
below). The initial trials
of the pipeline in
2014-2015 yielded immediate results:
a 7.5 meter diameter asteroid, less t
han 1/3 the distance to the Moon. See
figure below.
Caltech has built a new ½ Gigapixel CCD camera for the Palomar Schmidt
Telescope, the Zwicky Transient Facilit
y (ZTF), that has a 47 square degree
field of view, more that 6 times that
of the earlier came
ra. In addition, the
camera is more sensitive allowing 30
second exposures. For small asteroids,
the improvement in detection rate shoul
d increase by about x20. Instead of a
rate of about one small asteroid detecti
on per month, the rate should now be
about one per day. Althoug
h the possibility of an ARM mission is now less
probable, the scientific interest in char
acterizing the population of near earth
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asteroids is even higher. Surveys using the new Palomar Schmidt CCD camera
are be a major step forward in detecting small asteroids. This program would
not have been possible without the earlier
KISS funding. The ZT
F instrument will
begin survey operations in May 2018.
Waszczak, A., Prince, T.A., Laher, R
., Masci, F., Bue, B., Rebbapragada, U.,
Barlow, T., Surace, J., Helou, G. and
Kulkarni, S., 2017. Small near-Earth
asteroids in the Palomar Transient Factor
y survey: A real-time streak-detection
system. Publications of the Astronomical
Society of the
Pacific, 129(973),
p.034402 (2017).
Papers, published work
General References
Brophy, J.R., Friedman, L. and Cu
lick, F., 2012, March. Asteroid
retrieval feasibility. In
Aerospace Conference, 2012 IEEE
(pp. 1-16).
IEEE.
Brophy, John R. and Muirhead, Brian (2013)
Near-Earth Asteroid
Retrieval Mission (ARM) study.
In: 33rd International Electric
Propulsion Conference, October
6 - 10, 2013, Washington DC.
(Unpublished)
Papers related to Technical Development
Landau, D. and Dankanich, J. and St
range, N. and Bellerose, J. et
al (2013)
Trajectories to nab a NEA (Near-Earth Asteroid).
In:
AAS/AIAA Spaceflight Mechanics M
eeting, 10-14 Februrary 2013,
Kauai, HI.
Brophy, John R. and Friedm
an, L. J. and Strange,
Nathan and Prince, Thomas
A. et al. (2014)
Synergies of Robotic
Asteroid Redirection Technologies and Human Space
Exploration.
International Astronaut
ical Federation.
Brophy, J.R., Friedman, L., Stra
nge, N.J., Prince, T.A., Landau, D.,
Jones, T., Schweickart, R., Lewicki,
C., Elvis, M. and Manzella, D.,
2014. Synergies of Robotic Astero
id Redirection Technologies and
Human Space Exploration.
IAC-14.A5.3-B3.6.7 x26388 presented at
the 65th International
Astronautical Congress
, 2014.
Strange, N.J., Landau, D., Longuski, J. and Chodas, P., 2014.
Identification of retriev
able asteroids with the Tisserand criterion. In
AIAA/AAS Astrodynamics Specialist Conference
(p. 4458).
Mazanek, D.D., Merrill, R.G., Brophy
, J.R. and Mueller, R.P., 2015.
Asteroid redirect mission concept: a bold approach for utilizing
space resources. Acta
Astronautica, 117, pp.163-171.
9
Waszczak, A., Prince, T.A.,
Laher, R., Masci, F., Bue, B.,
Rebbapragada, U., Barlow, T., Sura
ce, J., Helou, G. and Kulkarni,
S., 2017. Small near-Earth asteroids in the Palomar Transient
Factory survey: A real-tim
e streak-detection system.
Publications of
the Astronomical Society of the Pacific
,
129
(973), p.034402 (2017).
Brophy, J. R., 2017.
Legacy of the Asteroid Redirect Mission
(ARRM). 35
th
International Electric Propulsion Conferece.
[Included
as an appendix.]
Presentations
There were numerous pres
entations on the ARM mission and technology. Two
early presentations are given here:
May 21, 2013, Testimony by Loui
s Friedman to the Subcommittee
on Space - Next Steps in Human Ex
ploration to Mars and Beyond
(2pm at 2318 Rayburn House Offi
ce Building Washington, D.C.
20515)
“Trending Topics in Space Technology”, Strathclyde Univ., Glasgow
by Marco Tantardini
March 28, 2013, Presentation
by Paul Dimotakis and Louis
Friedman on the KISS Study on Asteroid Return Mission to the
National Research Council Techni
cal Panel on Human Spaceflight,
The Keck Center, Washington DC.
Media Coverage
Media coverage of the ARM mission wa
s very extensive and the number of
press articles is too numerous to list
here, although a representative sample
may be found here:
http://kiss.caltech.edu/paper
s/asteroid/papers.html
External Funding
External funding proposed/received to c
ontinue work started with Keck Institute
funding.
A very significant amount of
NASA funding went towards the
development of the ARM concept, a di
rect result of the initial Keck
Institute study program. In FY
2014 alone, NASA budgeted over
$100M for development of the mission.
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Caltech President’s and Directo
r’s Fund for small NEA detection:
$597,540
NSF Growth Funding for small NEA detection: $390,000
IV. Future Work
The ARM technical work will continue as NASA funded development for space solar
electric propulsion. See Appendix B for
a detaled description of follow-on work.
The small NEA detection work will continue
as part of the Zwicky Transient Facility
(ZTF). Funding has been requested in the
past from NASA to support ZTF asteroid
work and a new proposal will
be submitted in June 2018.
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Appendix A: Documentati
on of Program Description
12
13
14
15
16
Appendix B: Documentati
on of Legacy of ARM
17
18
19
20
21
22
23
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