The DARPA briefing discusses advancements in space technology aimed at enhancing U.S. military capabilities and ensuring national security through innovative solutions such as affordable launches and space domain awareness. Key initiatives include programs like ALASA and XS-1, designed to reduce launch costs and improve access to space with air-launch capabilities and hypersonic vehicles. Furthermore, the agency emphasizes collaboration with commercial sectors and international partners to achieve agile and effective space operations.

1. On the Cusp: What’s Next
DARPA Perspective on Space
Ms. Pamela A. Melroy, Deputy Director, Tactical Technology Office
Briefing prepared for 53rd Robert H. Goddard Memorial Symposium
March 12, 2015
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2. The Defense Advanced Research Projects Agency (DARPA)
was established in 1958 to prevent strategic surprise
from negatively affecting U.S. national security and create
strategic surprise for U.S. adversaries by maintaining the
technological superiority of the U.S. military.
To fulfill its mission, the Agency relies on diverse
performers to apply multi-disciplinary approaches to both
advance knowledge through basic research and create
innovative technologies that address current practical
problems through applied research.
As the DoD’s primary innovation engine, DARPA
undertakes projects that are finite in duration but that
create lasting revolutionary change.
Mission
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3. • Current launch has no surge capability and long call-up times
• 2+ years to get “into the queue”
• Maserati custom-built production line of a few vs.
Ford assembly line of thousands
• Fixed launch sites are vulnerable
Flexibility Has Not Been a Priority
© Reuters
© NOAA
3
© Maserati
© NASA
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4. Space Domain Awareness (SDA) Today
~16,000+ objects in 1014 km3 (240,000 oceans)
GEO
MEO
Can characterize †
NumberofObjects
LEO
Known
objects in
LEO orbit
≈ 12,020
Can’t detect & track Can detect & track †
Can
characterize †Can’t detect & track Can detect & track †
Can characterize †Can’t detect & track Can detect & track †
4
Size of Objects (RCS m2)
U.S. satellites
International satellites
U.S. debris
International debris
KEY
† Cannot detect, track and
characterize every object
simultaneously
Known
objects in
MEO orbit
≈ 1,890
SWISSCUBE
RCS: 0.041 m2
COSMOS 2080
RCS: 1.0 m2
NAVSTAR 64
RCS: 6.3 m2
ISS
RCS: 227.8 m2
Vanguard 1
RCS: 0.11 m2
Known
objects in
GEO orbit
≈ 1,840
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5. Launch:
• Flexible, affordable access
• Affordable, routine and reliable access to space
• Aircraft-like space access to lower cost and increase capabilities
• Small satellite access to GEO
Satellite:
• Changing the paradigm of satellite operations
• New satellite architectures for speed and robustness
• GEO space robotics to repair and assemble very large satellites that could not be
launched
Space Domain Awareness (SDA):
• Real-time space domain awareness
• Real-time detection and tracking versus catalog maintenance and days to weeks of
forensics
DARPA Vision for Robust Space
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6. Flexible, Affordable Access to Space
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7. Artist’s concept
Airborne Launch Assist Space Access (ALASA)
ALASA aims to:
• Leverage performance, flexibility and re-
usability of air launch, and streamlined design
and manufacturing
• Reduce infrastructure costs by using runways
vs. fixed sites, automating operations;
avoiding unnecessary services
• Launch 100-pound payloads for under $1M
per flight, including range costs
• Have the satellite on orbit 24 hours after the
request
• Escape the constraints of fixed direction and
location for space launch
• Exercise the concept frequently enough to
make operations increasingly efficient and
cost-effective
Goal: Provide more affordable, routine and reliable access to space for multiple missions
Todays capabilities: Vertical launch
Future capabilities: Horizontal launch
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8. ALASA Design Emphasizes Features to Enable Lower
Unit Cost
• Two-stage liquid-fueled launch vehicle would use high
energy liquid monopropellant for simplified system
design and handling
• “Tractor” configuration would allow enhanced
performance
• Differential throttling and tangential canting would
eliminate gimbals and attitude jets
• Launching from unmodified F-15E aircraft would
leverage existing infrastructure for fast response and
low cost
• Commercial-grade avionics, advanced composite
structures, automated mission planning and flight
termination systems would reduce costs
Artist’s concept
Artist’s concept
Artist’s concept
Artist’s concept
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9. • ALASA had a successful Phase I, which resulted in three viable system designs and three
enabling technologies that continued on into Phase II (engine test and critical design
review)
• Payload depends on delivered engine performance with new monopropellant, which will be
verified by testing beginning in February 2015
• DARPA has approved Phase III: 12 orbital test launched in 2015 and 2016; the smallsat
community is excited about having dedicated launch opportunities, and there has been no
difficulty finding useful payloads
Summary
Artist’s Concept
Artist’s Concept
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10. XS-1 aims to:
• Break cycle of escalating space system
costs by:
• Enabling future space system
architectures
• Leveraging interests & capabilities of
commercial sector and space tourism
• Expand the reusable air-launched
concept with a hypersonic vehicle
capable of launching 3,000- to 5,000-
lbs payloads for $5M with low-cost
upper stage
• Mature and integrate technologies
supporting launch and hypersonic
vehicles
• Demonstrate mission assurance by
flying 10 times in 10 days
Experimental Spaceplane (XS-1)
Goal: Lower launch costs and increase space capabilities with aircraft-like space access
10
Artist’s Concept
Artist’s Concept
Artist’s Concept
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11. XS-1
Booster
Engine 2 Merlins
GLOW (K lbs) 223.9
MECO (K lbs) 47.4
Usable LOX/RP (K lbs) 176.5
Isp (vac) 310
Stage PMF 0.84
Upper Stage
GLOW (lbs) 15.0
Isp (vac) 336
Stage PMF 0.9
Payload (K lbs) 3.0 0 100 200 300 400 500 600
Altitude,Kft
Downrange, nmi
2-Stage Vehicle (GLOW-223.9K
lbs)
Booster (2-Merlins)
Propellant = 176.5K lbs
ISP (vac) = 310 sec
PMF = 0.84
Upper Stage (GLOW-15K lbs)
ISP (vac) = 336 sec
Staging:
Time = 169.9 sec
DR = 71.9 nmi
Altitude = 237,155 ft
Mach = 10.8
Payload = 3,025 lbm
100x100 nmi
28.5 deg Inclination
700
600
500
400
300
200
100
0
Notional X-Plane Upper Stage Trades
Expendable stage ~5%
of stack weight
Mach 10 staging with small upper stage (shown)
Alternative would be Mach 5 staging with larger upper stage
Artist’s Concept
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12. XS-1 Summary
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Artist’s concept
XS-1 aims to create a new paradigm for more routine,
responsive and affordable space operations
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Artist’s concept
Artist’s concept
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XS-1 seeks to:
- Address growing launch costs in an era of
declining budgets
- Lower operating costs to enable new,
game-changing capabilities
- Leverage emerging suborbital launch
technology & entrepreneurs
- Demonstrate technology for transition to
government and commercial users

13. Payload Orbital Delivery (POD) System
• A standardized mechanism designed to safely carry
and release in GEO a wide variety of payloads aboard
commercial communications satellites
• Increase opportunities for small mass (~70-100 kg) to
many orbits (including GEO):
• High-tempo launches
• POD payload is agnostic to launch vehicle,
interfacing instead with the GEO host spacecraft
• Provide opportunities for rideshare and separation
from a host:
• Adjustable, precise and reliable payload ejection
• Low POD tumble rates for safe release
• Low dynamic disturbance to host
• Increase responsiveness:
• Efficient integration, testing and qualification,
and minimized need for re-verification, allowing
for late integration to the hosting satellite
• Flexibility in payload geometry and CG location
13
Artist’s concept
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14. Changing the Paradigm of Satellite Operations
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15. Satlets
eXperiment for Cellular Integration
Technologies
(eXCITe)
Orbit: 450x720
98 deg
Date: 1QFY16
Life: 2-8 weeks
Launch: 1 of 5 payloads on a SHERPA
Objectives:
1. Demonstrate aggregation ability to withstand
launch environment, perform and maintain
thermal control, communicate with the ground,
reconstitute traditional spacecraft bus capability
2. Demonstrate aggregation ability to support a
simple and a complex payload
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Artist’s concept
Artist’s concept
• A new low-cost, modular satellite
architecture that can scale almost infinitely
• Satlets are small modules that incorporate
multiple essential satellite functions and
share data, power and thermal
management capabilities
• Satlets physically aggregate in different
combinations that would provide
capabilities to accomplish diverse missions
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16. • Provide unparalleled
high-resolution images
on request of spacecraft
experiencing anomalies
• Inspections would be
enabled by a RMMV with
a sensor suite and
dexterous arms with
cameras
• Stand-off inspections
(50m-1km)
• Close inspections (5m-
50m)
• Docked inspections
Future Goal: GEO Robotic Servicing
• Cooperatively move
spacecraft in orbit,
recover spacecraft in off-
nominal orbits and extend
lifetimes through
propellant conservation
• N/S station keeping
recovery
• End-of-Life to GEO
graveyard
• Repositioning within the
GEO belt
• Assist spacecraft
experiencing
anomalies, helping to
ensure that missions can
be completed at
maximum performance
• Free stuck appendages
• Supplement attitude
control
• Perform docked
inspections
Artist’s
Concept
Artist’s
Concept
Artist’s
Concept
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17. GEO servicing Could Build Confidence to
Transform the Entire Space ArchitectureSERVICING
First robotic
capability in GEO
Commercial
providers expand
coverage
NEWARCHITECTURES
LEO-to-GEO
space tug
• On-orbit replaceable units
• Modular spacecraft
Large apertures,
structures and bases
Automated,
scheduled
refueling
• Reduced
redundancy
• Lightly fueled
at launch
• Assembly
experiments
Technology development and investment
Space robotics = national-level growth potential
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18. Real-Time Space Domain Awareness
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19. OrbitOutlook
19
• Space Situational
Awareness (SSA)
currently uses
sophisticated and
exquisite certified
government sensors
• With this model,
greater coverage can
only come at a
significant cost Artist Concept
Government ground
based sensors
Joint Space
Operations Center
Government space
based sensors
Space object
Goal: Leverage hundreds of available, low-cost assets to increase coverage and
persistence of tracking space objects
Artist’s Concept
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20. OrbitOutlook
Government ground
based sensors
Commercial RF
tracking
University optical tracking
Joint Space
Operations Center
Data gathering
and analysis
International
partner data
Space object
Commercial
optical tracking
Artist’s Concept
Government space
based sensors
OrbitOutlook aims to:
• Integrate space
surveillance data from
non-traditional DoD
sources
• Commercial
• Academia
• International partners
• Establish processes to
verify information
assurance and data
quality
• Develop characterization
and Indications and
Warning (I&W)
techniques
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Goal: Leverage hundreds of available, low-cost assets to increase coverage and
persistence of tracking space objects
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21. Hallmark: Real-Time Space Domain Awareness
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Goals:
• Perform real-time information fusion,
including course of action (COA)
generation and execution support
• Ingest source-agnostic information
• Use automation algorithms as decision
aids to meet specific timelines
• Develop 3D visualization containing
intuitive commander operating picture
Provide U.S. senior leadership the tools needed for real-time understanding and evaluation
of the space environment
Artist’s Concept
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22. Creating the Future
Routine access to spaceGEO robotic servicing
Tactical space traffic control
DARPA space programs could help enable
breakthrough future technologies in many
areas, including:
• Tactical space traffic control
• GEO robotic servicing
• Routine access to space
DARPA seeks to fuel and leverage commercial
capabilities, and partner with other agencies to
augment national and economic security
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Artist’s concept
Artist’s concept
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Artist’s concept

23. www.darpa.mil
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