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Remote sensing space science enabled by the Multiple Instrument Distributed Aperture Sensor (MIDAS) concept

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The science capabilities and features of an innovative and revolutionary approach to remote sensing imaging systems aimed at increasing the return on future planetary science missions many fold are described. Our concept, called Multiple Instrument Distributed Aperture Sensor (MIDAS), provides a large-aperture, wide-field, diffraction-limited telescope at a fraction of the cost, mass and volume of conventional space telescopes, by integrating advanced optical imaging interferometer technologies into a multi-functional remote sensing science payload. MIDAS acts as a single front-end actively controlled telescope array for use on common missions, reducing the cost, resources, complexity, and risks of developing a set of back-end science instruments (SIs) tailored to each specific mission. By interfacing to multiple science instruments, MIDAS enables either sequential or concurrent SI operations in all functional modes. Passive imaging modes enable remote sensing at diffraction-limited resolution sequentially by each SI, as well as at somewhat lower resolution by multiple SIs acting concurrently on the image, such as in different wavebands. MIDAS inherently provides nanometer-resolution hyperspectral passive imaging without the need for any moving parts in the SI's. Our optical design features high-resolution imaging for long dwell times at high altitudes, <1m GSD from the 5000km extent of spiral orbits, thereby enabling regional remote sensing of dynamic planet surface processes, as well as ultra-high resolution of 2cm GSD from a 100km science orbit that enable orbital searches for signs of life processes on the planet surface. In its active remote sensing modes, using an integrated solid-state laser source, MIDAS enables LIDAR, vibrometry, surface illumination, ablation, laser spectroscopy and optical laser communications. The powerful combination of MIDAS passive and active modes, each with sequential or concurrent SI operations, increases potential science return for space science missions many fold. For example, on a mission to the icy moons of Jupiter, MIDAS enhances detailed imaging of the geology and glaciology of the surface, determining the geochemistry of surface materials, and conducting seismic and tidal studies.
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Remote Sensing Space Science Enabled by the Multiple Instrument
Distributed Aperture Sensor (MIDAS) Concept
Joe Pitman,a, Alan Duncana, David Stubbsa, Robert Siglera, Rick Kendricka, Eric Smitha, James Masona
Gregory Deloryb, Jere H. Lippsb, Michael Mangab, James Grahamb, Imke de Paterb, Sarah Reiboldtb
Edward Bierhausc, James B. Daltond, James Fienupe, Jeffrey Yuf
aLockheed Martin Advanced Technology Center, 3251 Hanover Street, Palo Alto CA 94304-1191
bCenter for Integrative Planetary Science, University of California, Berkeley CA 94720
cLockheed Martin Astronautics, Denver CO 80201
dSETI Institute, NASA/Ames Research Center, Moffett Field CA 94035-1000
eUniversity of Rochester, Rochester NY 14627
fJet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91109
ABSTRACT
The science capabilities and features of an innovative and revolutionary approach to remote sensing imaging systems
aimed at increasing the return on future planetary science missions many fold are described. Our concept, called
Multiple Instrument Distributed Aperture Sensor (MIDAS), provides a large-aperture, wide-field, diffraction-limited
telescope at a fraction of the cost, mass and volume of conventional space telescopes, by integrating advanced optical
imaging interferometer technologies into a multi-functional remote sensing science payload. MIDAS acts as a single
front-end actively controlled telescope array for use on common missions, reducing the cost, resources, complexity, and
risks of developing a set of back-end science instruments (SIs) tailored to each specific mission. By interfacing to
multiple science instruments, MIDAS enables either sequential or concurrent SI operations in all functional modes.
Passive imaging modes enable remote sensing at diffraction-limited resolution sequentially by each SI, as well as at
somewhat lower resolution by multiple SIs acting concurrently on the image, such as in different wavebands. MIDAS
inherently provides nanometer-resolution hyperspectral passive imaging without the need for any moving parts in the
SI’s. Our optical design features high-resolution imaging for long dwell times at high altitudes, <1m GSD from the
5000km extent of spiral orbits, thereby enabling
regional remote sensing of dynamic planet surface
processes, as well as ultra-high resolution of 2cm
GSD from a 100km science orbit that enable orbital
searches for signs of life processes on the planet
surface. In its active remote sensing modes, using an
integrated solid-state laser source, MIDAS enables
LIDAR, vibrometry, surface illumination, ablation,
laser spectroscopy and optical laser communications.
The powerful combination of MIDAS passive and
active modes, each with sequential or concurrent SI
operations, increases potential science return for
space science missions many fold. For example, on a
mission to the icy moons of Jupiter, MIDAS enhances
detailed imaging of the geology and glaciology of the
surface, determining the geochemistry of surface
materials, and conducting seismic and tidal studies.
Keywords: Remote Sensing Space Science,
Distributed Aperture Imaging Telescopes
joe.pitman@lmco.com, 650-424-2145
Telescope
(1 of 9)
Combiner
Multiple
Telescope
Array
(MTA)
Hexapod
Optical
Bench
Launch
Locks
Spacecraft
Interface
Figure 1 MIDAS Concept
Instruments, Methods, and Missions for Astrobiology VIII, edited by
Richard B. Hoover, Gilbert V. Levin, Alexei Y. Rozanov, Proc. of SPIE Vol. 5555
(SPIE, Bellingham, WA, 2004) · 0277-786X/04/$15 · doi: 10.1117/12.560290
301
INTRODUCTION
The design concept and key features of an innovative and revolutionary approach to remote sensing imaging systems,
aimed at increasing the return on future planetary science missions many fold, are described. Our Multiple Instrument
Distributed Aperture Sensor (MIDAS) concept, shown in Figure 1, provides a large-aperture, wide-field, diffraction-
limited telescope at a fraction of the cost, mass and volume of conventional telescopes, by integrating patented1 optical
interferometry technologies into a mature multiple aperture array concept that addresses one of the highest needs for
advancing future planetary science remote sensing2. MIDAS acts as a single front-end remote sensing science payload
for common missions, reducing the cost, resources, complexity, and risks of a set of back-end science instruments (SIs)
tailored to each specific mission. By interfacing to multiple science instruments, MIDAS enables either sequential or
concurrent SI operations in all functional modes. Passive imaging modes with MIDAS enable remote sensing at
diffraction-limited resolution sequentially by each SI, as well as at somewhat lower resolution by multiple SIs acting
concurrently on the image, such as in different wavebands. MIDAS inherently provides nanometer resolution
hyperspectral passive imaging without the need for any moving parts in the SI’s. The optical design features high-
resolution imaging for long dwell times at high altitudes, <1m GSD from 5000km extent of spiral orbits, thereby
enabling regional remote sensing of dynamic planet surface processes, as well as ultra-high resolution imaging at <2cm
GSD from the 100km science orbits, enabling orbital searches for life sign processes on the planet surface. For NASA’s
new class of Nuclear Electric Propulsion (NEP) missions, such as the Jupiter Icy Moons Orbiter (JIMO), MIDAS taps
the extensive NEP-enable power allocation for science with its active remote sensing modes, using an integrated solid-
state laser source, to enable LIDAR, vibrometry, surface illumination, and active or ablative spectroscopy science
investigations, integrated with the collection of back-end SI’s, as well as optical laser comm for science data return.
DESCRIPTION
1. Overall Description
The MIDAS payload architecture is shown in Figure 2. The MIDAS Science Payload Element is comprised of a
Multiple Telescope Array (MTA), a collection of back-end SI’s, and a common Command & Data Handling (C&DH)
subsystem. The MTA is comprised of its core Mechanical, Optical and Laser subsystems supported by a Pointing
Control Subsystem (PCS), Thermal Control Subsystem (TCS) and Electrical Power System (EPS).
The MIDAS concept3 in general, as shown in Figure 3, uses an array of collector telescopes together with relay optics, a
combiner, and a set of back-end SI’s to form an advanced remote sensing system. The 1.5m MIDAS point design uses
nine 35 cm aperture telescopes arranged in a circular sparse array having a 50% fill factor to form a synthetic aperture
of 1.5 m that is packaged within a compact payload volume of only 1.6 m diameter by 1.5 m long. A circular optical
bench provides a stable reference for the optical subsystem and back-end SI’s. When MIDAS is operational the optical
bench is supported and pointed by hexapods mounted from the spacecraft interface plate. These hexapods stow the
MIDAS payload element against launch locks to provide increased support and rigidity.
SI #1 SI #3
SI #2 SI #4 SI #6
SI #5
MTA
MIDAS Science
Payload Element
SI to MTA
Interfaces
Mechanical
Subsys
MIDAS to S/C
Interfaces S/C
Laser
Subsys
Collectors Combiner
Optical
Subsys
Relays
TCS
EPS
C&DH
PCS
Figure 2 MIDAS Payload Architecture
302 Proc. of SPIE Vol. 5555
2. Mechanical Subsystem Summary
The MIDAS mechanical subsystem integrates the optical, laser and support subsystems. A thermally stable graphite-
cyanate circular optical bench meters the telescopes, supports the beam combiner, and interfaces to each of the six back-
end science instruments. The optical bench is pointed with respect to the spacecraft via a hexapod assembly, made up
of six linearly actuated struts, allowing a +15 degree tip/tilt of the entire MTA relative to the spacecraft. The hexapod is
also used to stow the MTA onto three launch locks to increase structural rigidity and integrity when desired, such as
under launch load conditions. An interface plate mounts to the ends of the hexapod, making for a clean spacecraft
interface. All payload electrical harnessing connectors are located on this spacecraft interface plate.
3. Optical Subsystem Summary
The MIDAS concept further advances multiple telescope array optical systems. As shown in Figure 4, the 1.5m
MIDAS optical design uses a series of individual afocal collector telescopes, followed by a relay section with fixed and
active plano mirrors (all located in nominally collimated light), and finally a central combiner telescope to merge the
light from all apertures into a single phased image. The degree of aberration correction demanded for a distributed
telescope array to form an extended field image with proper phasing has been well investigated 4,5,6,7. The MIDAS
optical design has a number of unique features that provide significant benefits to planetary science remote sensing. It
has a large optical Field-Of-Regard (FOR) that is well corrected and it is capable of steering the detector’s field of view
(FOV) over this FOR with internal steering optics. MIDAS can also be used as a very high resolution imaging Fourier
transform spectrometer8,9, as it has internal pathlength control over each of its individual collector apertures.
Multiple US patents filed, pending and granted for MIDAS technology 1.6 m
1.5 m
35 cm
1.5 m Synthetic Aperture
Figure 3 MIDAS Overall Design Concept
Proc. of SPIE Vol. 5555 303
4. Laser Subsystem Summary
The MIDAS laser subsystem provides integral solid-state laser assemblies that can be used in planetary science
missions to provide varying degrees of active remote sensing. These capabilities range from broad area illumination at
one or more specific wavelengths of interest, such as for remote Raman spectroscopy or enhanced stereo imaging, to
ablation of small target areas on the planet surface, such as for ablative spectroscopy by the MIDAS back-end science
instruments. The laser subsystem enables the MIDAS array to illuminate portions of the planet surface for active
imaging. The laser subsystem also enables using active remote sensing techniques to probe the geomechanic
characteristics and behavior of the planet surface and its processes. MIDAS enabled LIDAR can significantly enhance
the surface coverage and accuracy of topographic measurements by means of the large effective aperture and collecting
area of the array. MIDAS enabled vibrometery similarly offers the possibility of active remote sensing of dynamic
planet surface processes of interest, such as the fluctuation of the planet surface due to tidal forces, by enabling not only
high resolution topography but doing so from high altitudes with large dwell times and repeatedly over the course of
years of spiral orbits on a mission like JIMO.
5. Pointing & Control Subsystem Summary
The MIDAS pointing & control subsystem (PCS) is comprised of a hexapod architecture scan platform consisting of six
actuated struts. Each strut contains a linear actuator with sufficient travel to allow the MTA an overall 15° FOR. The
actuator contains a preloaded, recirculating ball nut device utilizing either a low outgassing liquid or solid lubricant.
The actuator motor can be of the DC variety with an integral brake or stepper drive. The actuator is located between
graphite cyanate composite structural tubes. At the ends of each strut are flexured fittings used to reduce motion
deadband. One significant advantage of using a hexapod architecture is that it provides six degree-of-freedom motion
of the base with graceful degradation should any of the actuators fail. In this application the hexapod scan platform is
required only to provide overall tip and tilt control of the MTA, and its six available degrees of freedom are thus very
redundant. Any one failed actuator does not degrade pointing capability of the MTA at all, because the other five struts
fully enable tip and tilt control of the MTA through its entire FOR. Additional strut failures begin to limit the range of
MTA tip and tilt motions, to a degree that depends on which of the multiple actuators fail.
39.1 m, f/26EFL & F/no.
0.8 mLength (2)
50%Fill factor (1)
1.5 mDiameter (1)
MIDAS Optical Characteristics
39.1 m, f/26EFL & F/no.
0.8 mLength (2)
50%Fill factor (1)
1.5 mDiameter (1)
MIDAS Optical Characteristics
Notes
1. Based on circumscribed aperture
2. Collector secondary to combiner tertiary
Figure 4 MIDAS Optical Design
304 Proc. of SPIE Vol. 5555
The hexapod assembly drives the MTA to be supported on
three launch locks in the stowed configuration. This allows
the hexapod to be free of the additional requirement of
supporting the MTA through severe environments, such as
for the rigors of the launch environment. By doing this, the
hexapod assembly can be made lighter while the stowed
MTA can be made more compact, stiffer and stronger for
severe environments. The launch lock supports are
manufactured out of graphite cyanate composite and bolted
directly to the spacecraft interface plate. The redundant
launch locks can be any of the standard types: paired squib
pin pullers, nut separators or shockless paraffin actuators.
6. Science Instruments
The 1.5m MIDAS concept design accommodates up to six
back-end science instruments, as shown in Figure 5, that can
each sense and interrogate the optical image provided by the
MTA. The science instruments are individually, and if need
be also collectively, enclosed in one or more shields for
enhanced detector cooling and, when necessary, for radiation
protection. These science instruments can be configured
unique to the science needs of a specific planetary science
mission, while using the same MTA and pointing platform hardware that is common to a range of planetary science
missions, providing a balance between maximizing science return on specific missions like JIMO while minimizing
nonrecurring development and qualification costs for a collection of missions, such as for the Prometheus project.
The back-end SI’s occupy a volume dictated by a constraint on minimizing the overall science payload volume,
consistent with current JIMO resource allocations. For somewhat larger science payload volume allocations, the
individual SI’s can readily extend aft much further, with an associated increase in the spacecraft interface ring diameter.
HERITAGE
Figure 6 shows a full-scale lab testbed of a predecessor
radial telescope array developed at our Lockheed Martin
Advanced Technology Center (LM-ATC), used in
experiments to confirm performance and sensitivities of
multiple aperture concepts10. Many years of technology
development work on sparse aperture arrays11,12,13,
including advances at the LM-ATC such as the nine-
aperture testbed shown in Figure 7, have matured the
integration of optical interferometry technologies by
demonstrating diffraction-limited imaging with dilute
arrays, controllability of the entire optical system,
sensitivities, and practical aspects of design, packaging
and space-flight qualification. These and other testbeds
together with supporting component technology
development investments and advances have advanced
the application of distributed aperture sensing
approaches such as MIDAS to the needs and goals for
many-fold increased science returns on future planetary
science missions, such as the Prometheus class of NEP-
powered missions to the outer planets, led by JIMO.
Science
Instrument
(1 of 6)
Figure 5 MIDAS Concept Science Instruments
MIDAS_041
Figure 6 LM-ATC Radial Telescope Array Testbed
Proc. of SPIE Vol. 5555 305
KEY FEATURES AND BENEFITS
Key features and benefits of applying our MIDAS concept to planetary science missions are summarized in Table 1.
1. Resource Requirements
The 1.5m MIDAS MTA estimated mass (sized to accommodate and support six back-end SI’s) is about 250 kg,
depending on specific mission environments and requirements. The 1.5m MIDAS occupies 3.1 m3 of volume
(including a total science instrument volume of 0.125 m3), and measures 1.63 mφ by 1.53 m long. Extending the
instruments aft past the spacecraft interface plane can provide additional science instrument length, if needed. By
comparison, for any given aperture size, a conventional monolithic telescope (such as a Three-Mirror Anistigmat, or
TMA) of equivalent resolving power occupies three times the total volume of the MIDAS concept. In the axial
direction of the launch vehicle the MIDAS concept is three times more compact than a TMA, for a given aperture size,
simplifying packaging and integration.
Scene
Simulator
STAR-9
Telescope
Sensor
Suite
MIDAS_043
Support
Structure
9 Afocal Collector
Telescopes
Combiner and Sensor Suite
(behind support structure)
Figure 7 STAR-9 Distributed Aperture Testbed at LM-ATC
1.5m MIDAS Feature Benefit to Planetary science
Large FOR with steerable telescopes and MTA hexapod Global planetary surface mapping from high altitude
High resolution telescope with 1.5 m synthetic aperture Regional planetary surface mapping from science orbit
Six synchronized SI’s operating concurrently Multispectral imaging, SI redundancy
Fine UV/Vis/NIR hyperspectral imaging Global precise measure of planet surface composition
Active imaging modes (spectroscopy ,LIDAR, vibrometry) Remotely determine features, composition, topography
Large aperture collecting area of 1.8 m2 Greater throughput enables active imaging/spectroscopy & laser comm
Compact length less than 33% of a comparable aperture TMA Enhances structural efficiency, packaging, and pointing stability
Nine 35 cm telescopes form a 1.5 m effective aperture Lower cost than 1.5 m primary and lower risk than TMA secondary
Staring optical system, compared to scanners High quality and high rate planetary science data return
Modular design with clean interfaces to SIs and S/C Simplifies Integration & Test activity cost and schedule
Extensive use of heritage components Reduces recurring cost and development risk
Highly scalable design for specific mission needs Enables incremental payload development toward complex missions
Table 1 Key Features and Benefits of Applying MIDAS to Planetary Science Missions
306 Proc. of SPIE Vol. 5555
2. Planetary Science Capabilities
Implementing a MIDAS approach on future planetary science missions, such as the Prometheus class, enables a wide
range of science operating modes, features and capabilities. Implementing these capabilities depends on the science-
driven needs that determine the selection of a mission-specific collection of back-end SI’s, and the end-to-end optical
system features chosen for performance optimization. The combination of MIDAS passive and active modes, each with
sequential or concurrent SI operations, offers the opportunity to increase potential science return for planetary science
missions many fold. For example, on a mission to the icy moons of Jupiter as shown in Figure 8, MIDAS aligns well
with top level science requirements14 by providing high-resolution wideband imaging of the geology and glaciology of
the surface15,16, high spectral resolution to help determine the geochemistry of surface materials17, active spectroscopy
techniques18 to help in the search for signs of life processes19, active imaging to help conduct seismic and tidal studies20,
and high optical throughput to enable laser comm approaches for science data return. The MIDAS concept helps
maximize the science data return on future planetary science missions such as JIMO, one of the Prometheus-class
missions planned by NASA to use NEP. This potential increased science return is made possible by NEP enabling
significantly increased mass and power resources allocated to the science payload, as well as enabling extended duration
of near-constant science data taking, which is about 4 years in the Jovian system for the current JIMO baseline mission,
as shown in Figure 9. These missions use NEP to achieve relatively large amounts of propulsion capability at the outer
planets, allowing an advanced remote sensing approach like MIDAS to have extended and extensive observation
campaigns from a range of altitudes and phase angles, aligning very well with the primary and secondary science
objectives. By featuring such fine spatial and spectral resolution capability, Figure 8, MIDAS enables not only orders
of magnitude better resolution from the 100km science orbit than previously obtained at the outer planets, but also about
2 years of science data taking at better than 1m resolution during the spiral orbits around each icy moon at Jupiter.
MIDAS_023H
AAA
AAA
AAA
AAA
AAA
AAA
Key JIMO Science Goals MIDAS 1.5m Design Capabilities
Icy Moon
Global Mapping of Moons
Imaging (UV/Visible/IR)
Spectroscopy (0.2 to 15µm)
Thermal Emissions
Regional Mapping of Moons
Imaging (UV/Visible/IR)
Spectroscopy (0.2 to 15µm)
Concurrent Ops for 6 SI’s
Global Mapping
Regional Mapping
Laser Active Imaging
Jovian Remote Sensing
Imaging from Icy Moons
Concurrent Mode
Medium Resolution
Focal Plane
Telescope Array
Phased Mode - Single Image
<1m GSD of Entire Moon @ 5000km
~1nm of Entire Moon @ 5000km
Map Entire Moon @ 5000km
Phased Mode – Single Image
2cm GSD of 26km Area @ 100km
~1nm of 26km Area @ 100km
Concurrent Mode – 9 Shared Images
<4m GSD of Entire Moon @ 5000km
<8cm GSD of 26km Area @ 100km
LIDAR, Vibrometery, Illumination
Phased Mode – Single Image
Io <50m GSD, Jupiter <130m GSD
Instruments
A
AA
A
A
A
A
A
A
A
AA
A
A
A
A
A
A
1 of 9
Telescopes
1 of 6 SI's Combiner
Phased Mode
High Resolution
or
A
0.01
0.1
1
10
100
1000
10000
100 1000 10000
Orbit Altitude (km)
Mapped Coverage (km, FOR)
Instantaneous Coverage (km, IFOV)
Resolution (meters, GSD)
0.01
0.1
1
10
100
1000
10000
100 1000 10000
Orbit Altitude (km)
Mapped Coverage (km, FOR)
Instantaneous Coverage (km, IFOV)
Resolution (meters, GSD)
MIDAS 1.5 m
Point Design
A
Figure 8 MIDAS Key Features & Benefits to Planetary Science Missions
Proc. of SPIE Vol. 5555 307
When considered in the context of the astrobiological search for signs of life processes, for example on Jupiter’s icy
moon Europa, the MIDAS approach shines, as captured in Figure 10. Because the reference JIMO mission while in the
Jovian system spends much of its time in steadily decreasing and then steadily increasing altitude spiral orbits at each of
the icy moons, very high resolution systems like MIDAS can enable a strategy of undertaking high-altitude <1m
resolution global and regional imaging and spectral characterization for months while in spiral orbits, followed by
spending time understanding the results of those observations to guide subsequent months of regional and local imaging
down to 2cm resolution and spectral characterization of features having the most value and interest from the science
orbit at each moon. The power of 2cm GSD resolution from a 100km science orbit at each of Jupiter’s icy moons is
highly leveraged by proceeding and following each of those science orbits with months of observations taking at <1m
GSD resolution achieved during the inward and outward spiral orbits extending to 5000km altitude.
3. Growth and Scalability
The MIDAS concept is highly scalable to a wide range of growth configurations. For space-based science mission
applications, MIDAS readily scales with very little change to about 5m in synthetic aperture, with the upper end
limitation imposed by existing launch vehicle payload fairing diameters. This upper limit could readily grow to about
7m if industry efforts now underway at developing 7m diameter fairings prove successful. Above this limit imposed by
launch vehicle payload fairing diameters, MIDAS scales readily to well over 10m synthetic apertures by implementing a
change from fixed to deployable collector telescopes, such as put forth in one of our prior concepts21.
Indeed, applications of MIDAS technology are not limited to only space-based science missions, as evidenced by
continued interest and development of concepts for terrestrial-based distributed aperture optical systems22. The
advantages afforded distributed aperture approaches to the ever-increasing desire for higher resolution and total optical
throughput, including their compact volume, lower mass, reduced cost, and modularity benefits for maintenance and
upgrades, extend across the entire spectrum of planetary science remote sensing future needs.
Callisto
Ganymede
Europa
Io
Jupiter
Global Dark
Smooth Unit
Dense Large
Crater Population
Dark Terrain
Light Terrain
Caldera ??
Ridges
Chaos
Volcanism
old
young
very young
middle aged
Environment & Weathering
Origin/Evolut ion of Icy Moons
Hyperspectral Imaging at 1nm Spectral and
2cm Spatial Resolution for ~7 Months from
100km Icy Moons Science Orbits
UV/Visible/NIR Imaging at 2cm to 1m Spatial
Resolution for ~22 Months from Spiral Orbits
Concurrent Imaging in 9 Channels and 6 SI's
at 6cm to 3m Resolution for ~29 Months in
Science Orbits and Spiral Orbits
Active Imaging from Science Orbits
Search for Sign s of Life
MIDAS CapabilitiesPrimary JIMO Science
Environment & Weathering
Origin/Evolut ion of Icy Moons
Hyperspectral Imaging at 1nm Spectral and
2cm Spatial Resolution for ~7 Months from
100km Icy Moons Science Orbits
UV/Visible/NIR Imaging at 2cm to 1m Spatial
Resolution for ~22 Months from Spiral Orbits
Concurrent Imaging in 9 Channels and 6 SI's
at 6cm to 3m Resolution for ~29 Months in
Science Orbits and Spiral Orbits
Active Imaging from Science Orbits
Search for Sign s of Life
MIDAS CapabilitiesPrimary JIMO Science
Jupiter Atmosphere Dynamics
Io Surface Features
Io Composition/Distribution
Hyperspectral Imaging at 1nm Spectral Resolution and
Spatial Resolution of ~50m for Io and ~130m for
Jupiter Lasting Up To ~27 Months During Icy Moon
Transfer Orbits
Concurrent Imaging in 9 Channels and 6 SI's at Spatial
Resolution of ~150m for Io and ~400m for Jupiter
Lasting ~27 Mont hs During Icy Moon Transfer Orbits
Io Active Volcanism
MIDAS CapabilitiesSecondary JIMO Science
Jupiter Atmosphere Dynamics
Io Surface Features
Io Composition/Distribution
Hyperspectral Imaging at 1nm Spectral Resolution and
Spatial Resolution of ~50m for Io and ~130m for
Jupiter Lasting Up To ~27 Months During Icy Moon
Transfer Orbits
Concurrent Imaging in 9 Channels and 6 SI's at Spatial
Resolution of ~150m for Io and ~400m for Jupiter
Lasting ~27 Mont hs During Icy Moon Transfer Orbits
Io Active Volcanism
MIDAS CapabilitiesSecondary JIMO Science
Local Imaging in
All Science Orbits
Global-Regional Imaging
in All Spiral Orbits
Extended Mission Science
• Europa Quarantine Orbit
• Transit to Io
Jovian Science in
All Transfer Orbits
Atmosphere
Dynamics
Spirals 30%
Transfers 55% On-Orbit 15%
14.6 Mo nths
26.5 Months 7 Months
Spirals 30%
Transfers 55% On-Orbit 15%
14.6 Mo nths
26.5 Months 7 Months
MIDAS_042B
Composition
Figure 9 Reference JIMO Mission Spends About 4 Years in Near-Continuous Science Data Taking Modes
308 Proc. of SPIE Vol. 5555
SUMMARY
We have described our Multiple Instrument Distributed Aperture Sensor (MIDAS) concept, which represents an
innovative approach to future planetary science mission remote sensing that enables order of magnitude increased
science data return. With its large-aperture, wide-field, diffraction-limited telescope packaged at a fraction of the cost,
mass and volume of conventional space telescopes, MIDAS helps advance the application of integrated optical imaging
interferometer technologies toward the goals of many-fold improved science data return on future planetary science
missions such as the Prometheus class of outer planet explorations, led by JIMO. The combination of ultra-high
resolution passive imaging, hyperspectral imaging, multispectral imaging, and various active sensing modes including
LIDAR, ablative spectroscopies and vibrometry, along with the ability to support active laser communication with high
optical throughput, make MIDAS the ideal choice for an integrated remote sensing science payload on future planetary
science missions to the outer planets.
0.0001 0.001 0.01 0.1 1 10 100 1000 10000 100000 1000000
Feature Size (m) and MIDAS Resolution (m)
10.0
1000.0
10000.0
Flight Altitude (km)
Features & Ejecta Distribution
Surface Bulging
Feature Relationships
Impact Craters
Correlation - Layers
Correlation - Stratigraphy
Diapirs
Contact Zones
100.0
Canyons
Cracks
Stratification Layers
Laminae
Anchor Ice
Slurry & Brine
Potential Landing Sites
Ice Pores and Channels
Grooved Terrains, Lineaments
Geologic Features Habitat Features
MIDAS_029D
Faults & Offsets
Ejecta, Flows, Etc.
Colored Terrains
Regolith, Mass Wasting
Sediment Texture, Maturity
Grain Size (Wentworth Scale)
Boulders
1.5m MIDAS Point
Design Resolution
At Altitude
Cracks, Fissures & Canyons
All Features
Resolved
Pebbles
Examples of : Geologic and Habitat Features
Polar Features
Tectonic Movements
Sand 2.0 cm GSD
On-orbit Limit
JIMO Science
Orbits (7 months)
JIMO Spiral
Orbits (14 months)
Figure 10 Geologic and Astrobiologic Features of Interest are Resolved with MIDAS for the Entire 4-year JIMO
Science Mission, Because Ultra-High Resolution Leverages the Value of Time Spent at High Altitudes
Proc. of SPIE Vol. 5555 309
REFERENCES
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2 Meyer, C. et. al. (1995) Planetary Surface Instruments Workshop LPI Pub 95-05.
3 Stubbs, D. et. al., Multiple Instrument Distributed Aperture Sensor (MIDAS) Science Payload Concept, SPIE paper
5487-201, June 2004.
4 Lucke, R. L., Fundamentals of Wide-Field Sparse-Aperture Imaging. US Naval Research Lab.
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