Attachment A - Statement of Work.pdf

AOS Polarimeter Instrument Study SOW AOSP-POLAR-SOW-0007, Revision -

Effective Date: May 31, 2023 i

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AOS-P Polarimeter Instrument Phase A Study

Statement of Work

Review/Signature/Approval Page

Prepared by:

Kirk Knobelspiesse

Reviewed by:

Bonnie Bradley

Scott Braun

Jonathan Bryson

Shelly Calabrisi

Daniel Cecil

William (Bill) Cook

Melody Djam

Brian Frey

Paul Geithner

Brian Lounsbury

Johnny Medina

Jeff Piepmeier

Dustyn Strosnider

James Sturm

Approved by:

Jeff Piepmeier

*** Electronic signatures are available on-line at: https://ipdtdms.gsfc.nasa.gov ii

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Preface

This document is under the AOS project configuration control. Once this document is approved, AOS project-approved changes are handled in accordance with Class I and Class II change control requirements, as described in the AOS Configuration Management Procedures and

Guidelines, and changes to this document shall be made by complete revision.

Any questions should be addressed to:

AOS Configuration Management Office

NASA GSFC

Code 425

Greenbelt, MD 20771 iii

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Change History Log

Revision Effective Date Description of Changes

(Reference the CCR & CCB/ERB Approval Date)

Revision - 05/31/2023 Baseline release following the approval of AOSP-CCR-iv

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Table of TBDs/TBRs/TBSs

[Required when TBDs/TBRs/TBSs are in Doc]

Action

Item

No.

Location Summary

Individual/

Organization

Actionee

Due Date v

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Table of Contents

1 BACKGROUND

1.1 AOS Mission Concept

1.2 Instrument Study Objectives / Top-Level of Work Required

1.3 Guiding Assumptions for Cost and Schedule

1.4 Study Milestone Schedule

2 DOCUMENTS

2.1 Applicable Documents

2.2 Reference Documents

3 STUDY ASSUMPTIONS AND OVERVIEW

3.1 Orbit and Attitude

3.2 Design Life and Risk Classification

3.3 Environments

3.4 Deployments

3.5 Spacecraft to Instrument Interface Assumptions

3.6 Technology Readiness Level

3.7 Instrument Performance and Constraints

4 WORK TO BE PERFORMED

4.1 Design Concept Development and Related Analyses

4.2 Feasibility and Trade Studies

4.3 Technology Readiness, Heritage, and Engineering Development

4.4 Risk Reduction and Demonstration

4.5 Management, Cost and Schedule

5 PERFORMANCE PERIOD, DELIVERABLES, AND REPORTING SCHEDULE

5.1 Reviews, Reporting, and Deliverables

5.2 Status Meetings and Reviews

5.3 Contract Data Requirement List (CDRL)

6 ABBREVIATIONS AND ACRONYMS

7 ATTACHMENT B

List of Figures

Figure 1. ESO Core Mission Areas for AOS

Figure 2. AOS Constellation with Planned International Partner SC

Figure 3. Beta Angle Variation Over Time

Figure 4. Eclipse Duration

Figure 5. Altitude and Latitude – Both Geocentric and Geodetic

Figure 6. Expected Geodetic Altitude Variation

List of Tables

Table 1. Classic (Brouwer Lyddane J2 Mean) Orbital Elements for AOS-P vi

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Table 2. Spacecraft to Instrument Interface Assumptions

Table 3. Contract Data Requirement List

Table 4 Summary of Polarimeter Target Characteristics

Table 5: Target Instrument Physical Resource Allocations

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1 BACKGROUND

1.1 AOS Mission Concept

The Earth System Observatory (ESO) Atmosphere Observing System (AOS) mission provides transformative three-dimensional space-based and suborbital observations of essential collocated dynamic, cloud, convection, precipitation and aerosol processes, leading to improved predictions of weather, air quality, and climate for the benefit of society.

In the report of the 2017-2027 “Decadal Survey (DS) of Earth Science and Applications from

Space” by the National Academies of Sciences, Engineering, and Medicine, questions central to understanding these processes were identified as top priories to address in the coming decade.

Five designated observables (DO) were declared to be of highest priority for the decade and will be studied within the ESO. Two of these DOs, Aerosols (A) and Clouds, Convection, and

Precipitation (CCP), are the core mission areas of AOS (see Error! Reference source not found.). Because the science and phenomena of these two AOS DOs are strongly intertwined, NASA executed a single combined Aerosol, Clouds, Convection, and Precipitation (ACCP) study aimed at addressing key questions and science objectives through synergistic measurements.

Figure 1. ESO Core Mission Areas for AOS

The ACCP study envisaged a mission architecture comprised of a space segment implemented as a constellation of multiple observatories in two orbit planes, one inclined (I) and one sun-synchronous polar (P), complimented by a significant suborbital segment. The space segment, as constituted at Key Decision Point A”, is depicted in Figure 2. It consists of four observatories carrying multiple scientific instruments, provided by NASA and international partners. NASA’s

AOS-Inclined (AOS-I) observatory and the Precipitation Measuring Mission (PMM) provided by the Japan Aerospace Exploration Agency (JAXA) will launch together on a NASA-provided launch vehicle. AOS-I will carry a scientific instrument provided by the Centre National d’Etudes Spatiales (CNES – the French National Space Agency). NASA’s AOS-Polar (AOS-P) observatory and the High-altitude Aerosols, Water vapor and Clouds (HAWC) observatory

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provided by the Canadian Space Agency (CSA) will launch together on another NASA-provided launch vehicle. AOS-P will carry a scientific instrument provided by CSA.

Figure 2. AOS Constellation with Planned International Partner SC

The risk classification of the NASA-provided AOS-I and AOS-P observatories is ‘Class C’ per

“Risk Classification for NASA Payloads” (NPR 8705.4A). The AOS-P will have a 3-year design life with sufficient consumables to enable a 5-year life. AOS-I is scheduled to launch before

AOS-P, and while there may be operational overlap between the two observatories there is currently no requirement for it. Once their operational science phases are completed, each

NASA-provided observatory will be decommissioned in accordance with "NASA Procedural

Requirements for Limiting Orbital Debris and Evaluating the Meteoroid and Orbital Debris

Environments” (NPR 8715.6).

The AOS suborbital (SUB) segment uses ground and aircraft-based instruments and sensors to support science objectives and environmental monitoring activities by providing measurements that can be done better or only from SUB platforms. The SUB instruments also will be used for

AOS-I and AOS-P instrument calibration and product validation.

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1.2 Instrument Study Objectives / Top-Level of Work Required

The purpose of the Polarimeter Instrument study is to provide insight into potential instrument concepts that will support AOS-P mission implementation, the degree to which the concepts meet performance targets, and maturity and risks of the concepts Risk Reduction &

Demonstration activities as determined by the proposer can provide mitigations of identified risks due to design maturity or other factors. The study results will be used to improve the technical and programmatic requirements in a potential Polarimeter Instrument request for proposal.

The intent of the study is to inform the government as to the feasibility and risks associated with current Polarimeter requirements and resulting design concepts. Specific areas of interest include:

1. Key and driving requirements, how they affect design, performance, and risks.

2. Analysis showing where performance and accommodation requirements can be or cannot be met.

3. Instrument design concept, including stowed and deployed configurations (where applicable), mass properties, and power, data rate, keep out zone (KOZ) and field of view

(FOV), and power and data rates (or volumes).

4. Technical maturity and risk areas of the instrument design concept.

5. Cost factors of the instrument design concept.

6. Risk Reduction and Demonstration (RR&D) through designing, analyzing, breadboarding, prototyping and/or testing key or driving systems, subsystems, boards, components and/or mechanisms.

7. Development plans and timeline including unique supply chain and/or long-lead procurement considerations.

1.3 Guiding Assumptions for Cost and Schedule

The Flight hardware development cost and schedule estimates shall be based on the following assumptions:

• One proto-flight unit and spare parts as per sparing philosophy proposed by the vendor through the study.

• Any additional Engineering Development Units (EDUs) or Engineering Test Units

(ETUs) needed throughout flight development for risk mitigation activities proposed by the vendor.

• Deliveries and support will be as shown in the following schedule – Note that the flight instrument development schedule with the earliest achievable delivery date meeting requirements will be provided by vendor..

Milestone Date (assume 1st day of quarter)

Flight contract award Q1 CY2025

Obs I&T Duration (post-delivery support)

16 months

Pre-launch duration (post-delivery support)

3 months

Commissioning support duration 3 months

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• No Government Furnished Equipment (GFE) will be provided.

• AOS comprises multiple payloads, which schedule estimates will be used to develop an earliest launch date.

1.4 Study Milestone Schedule

The study period of performance is divided into two main efforts: concept study and risk reduction and demonstration (RR&D). The contractor shall execute the study (as described in

Section 4) in accordance with the following milestone schedule. Requirements and deliverables for these milestones are described in Section 0.

Milestone Schedule

Kickoff meeting Within two weeks of award

Weekly Informal status meeting Every week after kickoff

Formal Monthly status meeting Formal status review

Check Point-1 Award + 2 months

Check Point-2 Award + 4 months

Concept Study Report Package -

Draft

Award + 4 months

Concept Study Report Package

(Study completion)– Final

Award + 5 months

RR&D Kick-off meeting Within the first 4 months after contract award

Bi-weekly Informal RR&D status meeting/ progress report

Bi-weekly after the start of Risk reduction activity

RR&D formal Progress Report- 1 Award + 7 months

RR&D Formal Progress Report- 2 Award + 9 months

RR&D Formal Progress Report- 3 Award + 11 months

RR&D Formal Progress Report- 4 Award + 13 months

RR&D Report - Final Award + 15 months

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2 DOCUMENTS

2.1 Applicable Documents

Document Number Title

Attachment B Atmosphere Observing System-Polar Polarimeter Performance

Targets and Technical Resource Allocations

2.2 Reference Documents

Document Number Title

GSFC-STD-1001A Criteria for Flight and Flight Support Systems Lifecycle Reviews

GSFC-STD-1000G GSFC Rules for the Design, Development, Verification, and

Operation of Flight Systems

GSFC-STD-7000A General Environmental Verification Standard (GEVS) for GSFC

Flight Programs and Projects

NPR 8705.4A Risk Classification for NASA Payloads

NASA SP-20205003605 Technology Readiness Assessment Best Practices Guide

NPR 7123.1C NASA Systems Engineering Processes and Requirements

(w/Change 1)

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3 STUDY ASSUMPTIONS AND OVERVIEW

This section provides mission design information and assumptions that shall be used for instrument concept development and concept of operations for the proposal. This reflects the baseline mission; however, modification to some of these parameters are explored via trade studies defined in Section 4.2. The Government will provide additional documentation after contract award including Environmental Requirements, Concept of Operations, and Design

Reference Mission, etc.

3.1 Orbit and Attitude

AOS-P will launch into a polar sun synchronous orbit with approximate altitude of 450 km and

13:30 LTAN. The orbit semi-major axis will be controlled to a tolerance of +/-10 km and is planned to have frozen eccentricity and argument of periapse. Any analyses can assume the orbital elements shown in Error! Reference source not found.. Note that the epoch aligns with an assumed start of science operations.

Table 1. Classic (Brouwer Lyddane J2 Mean) Orbital Elements for AOS-P

Orbit Element Units Value

Epoch UTC March 20, 2031 00:00:00

Semi-Major Axis (a)* km 6828 ± 10

Eccentricity (e) for frozen orbit N/A ≤ 0.0011

Inclination (i) degrees 97.2

Right Ascension of the Ascending Node () degrees ~ 19.4

Argument of Periapse () degrees 90

Mean Anomaly (MA)** degrees ~0 Notes:

* Based on a 450 km altitude above the Earth’s equatorial radius of 6378 km

** Arbitrarily set to 0 deg

3.1.1 Beta Angle

The angle with respect to the spacecraft’s orbital plane around the Earth-Sun vector is referred to as the beta angle (β). The beta angle determines the percentage of time that a satellite in low

Earth orbit (LEO) spends in direct sunlight and drives eclipse durations.

Because of orbital perturbations, the line of nodes for AOS-P will rotate at ~1 degree/day in a posigrade direction. This results in only small beta angle variations, as depicted in Figure 3.

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Figure 3. Beta Angle Variation Over Time

3.1.2 Eclipse

In this sun synchronous orbit, eclipse variations are relatively minimal and representative eclipse durations are depicted in Figure 4.

Figure 4. Eclipse Duration

3.1.3 Geocentric and Geodetic Height Variation

For SC in low Earth orbit (LEO), orbit altitude is expressed as the height of the SC above the surface of the Earth. However, that height can be defined as either geocentric or geodetic altitude. Unless otherwise specified, AOS-P assumes geodetic altitudes.

Similarly, latitude can be expressed as either geocentric or geodetic. Geocentric latitude being defined as the angle formed between the Earth equatorial plane and a line from the center of the

Earth to a point on the Earth’s surface. Alternatively, the geodetic latitude of a point is defined as the angle formed by the equatorial plane and a line passing through the point on the surface and which is normal to the surface.

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The AOS-P nominal mission altitude of 450 km is specified over the Earth’s equatorial radius of

6378 km, leading to a defined semi-major axis of 6828 km. Note that at the equator, there is no difference between geocentric or geodetic altitude and latitude.

Figure 5 shows the geocentric altitude of a SC (Hc), the geodetic altitude of the same spacecraft

(Hg), the geocentric latitude (c) of the geocentric sub-spacecraft point, and the geodetic latitude

(g) of the geocentric sub-spacecraft point.

Figure 5. Altitude and Latitude – Both Geocentric and Geodetic

Instrument performance needs to be evaluated over the full range of expected geodetic altitudes associated with the orbit as defined in this section. Figure 6 shows the expected geodetic altitude variation associated with the nominal 450km ± 10km orbit defined in Section 3.1.

Figure 6. Expected Geodetic Altitude Variation

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3.1.4 Target Attitude and Pointing Considerations

The target attitude for the AOS-P Spacecraft is geodetic nadir. Instruments may prefer static and/or dynamic off-pointing from this direction to achieve performance requirements. Static offset pointing should be assumed to be the responsibility of the instrument (i.e., accounted for in mechanical structure). Dynamic pointing (e.g., yaw to align an instrument axis with ground track) may be performed by the spacecraft bus at the request of the instrument teams, if needed.

3.2 Design Life and Risk Classification

Each AOS instrument payload is to be Risk Class C per NPR 8705.4, Appendix D. The mission design life of the instrument is 3 years minimum, with a 5-year design life for any consumables and/or life limited items.

3.3 Environments

It should be assumed that AOS-P will launch on one of the following Launch Vehicles: SpaceX

Falcon 9, Blue Origin New Glenn, and ULA Vulcan Centaur. Environments are to envelope all potential launch vehicle options. Specific environmental requirements will be provided during the study that will encompass the launch and on-orbit environments.

3.4 Deployments

Deployments for initial instrument configuration are acceptable and should be noted by the vendor. For example, this might include protective aperture covers or release mechanisms for a system locked during launch. The instrument should retain with the instrument any deployed hardware. No hardware is to be released into orbit under normal operations.

3.5 Spacecraft to Instrument Interface Assumptions

Table 2 provides assumptions that the instrument teams should use for the spacecraft to instrument interfaces.

Table 2. Spacecraft to Instrument Interface Assumptions

Identifier Category Spacecraft Interface Assumptions

AOS-1 Thermal Interface Instrument is responsible for its own thermal management, including any cryocoolers, operational heaters, thermal radiators, thermal straps, and heat pipes. Assume that spacecraft will accommodate field of view for instrument radiators with view to a 'cold side' of the spacecraft. Conductive heat transfer between instrument and mounting interface may be restricted.

AOS-2 Survival Heaters Spacecraft will provide dedicated, unswitched power feed(s) for survival heaters from nominal 28 V DC power service(s). Instrument is responsible for providing its own survival heater and control hardware (e.g.

thermostats).

AOS-3 Operational Power

Service

Assume nominal 28 V DC power service(s) from spacecraft battery system, notionally 26 V to 35 V DC range of variation.

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AOS-4 Power Service

Overcurrent Protection

All switchable power services from the spacecraft will implement resettable overcurrent protection (e.g. circuit breakers)

AOS-5 Instrument Thermal

Monitoring

The spacecraft will provide a set of spacecraft-read thermistors for thermal monitoring, regardless of the instrument powered state

AOS-6 Science Attitude The spacecraft will maintain a nadir-pointing attitude during science operations. Geodetic or geocentric nadir pointing can be considered based on preference of instruments. Should any static off-point or bias be required, it is to be provided by the instrument mechanical structure.

AOS-7 Calibration Activities Attitude slews for instrument checkout or calibration activities will be performed as needed. Instrument solar keep out zones and/or restrictions need to be documented for all instruments. This includes hard constraints

(e.g. solar impingement results in instant damage/degradation) and time-dependent constraints (e.g. sun slew through FOV must be at a certain rate or greater)

AOS-8 Science Data

Management

Assume spacecraft will provide the data record for all instrument science, telemetry, housekeeping for periodic spacecraft downlinking via a spacecraft-provided RF Communication system.

AOS-9 Science Data

Compression

Assume that the spacecraft will not implement any data compression on the instrument science data. The instruments may wish to implement data compression (lossy or lossless) algorithms prior to transfer to the spacecraft. Data Rate values provided in the targeted resource allocation are for overall data, regardless of whether it is compressed or uncompressed

AOS-10 Contamination Adequate precautions will be taken during Integration & Testing (I&T) to assure the on-orbit performance of the instruments. Materials used will be selected to be consistent with meeting low outgassing rates. Cleaning operations will be performed as necessary. It should be assumed that the observatory will be bagged when not in a Class 10,000 environment.

AOS-11 Electrical & Data

Interfaces

The instrument should assume that the spacecraft will provide the following electrical interfaces to each instrument:

1. +28 V primary power service(s) sized for instrument power

2. Data interfaces (e.g. RS-422, SpaceWire, etc.) for instrument command and telemetry

3. High-speed data interface sized for instrument data rate (e.g.

SpaceWire, LVDS, etc.)

4. Pulse Per Second (1 PPS) service(s) for time synchronization

5. Discrete commanding as requested AOS-12 Fault Protection The spacecraft provides system level monitors to safe the observatory, including safing and/or powering off instruments

AOS-13 Fault Isolation Faults should not propagate across the spacecraft/instrument interface.

Instrument failure modes must be assessed both within the instrument and at this interface.

AOS-14 ATS Commanding The spacecraft provides an Absolute Time Sequence (ATS) functionality to send pre-canned, time-tagged commands to the spacecraft and instruments.

Used for time sensitive commanding or sequences that need to be executed outside of contact.

AOS-15 CCSDS Compliance The Spacecraft will be compliant with Consultative Committee on Space

Data Systems (CCSDS) standards for communication

AOS-16 Launch Orientation The instrument will be mounted to the spacecraft such that the nominal instrument viewing direction is nearly normal to the launch direction.

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3.6 Technology Readiness Level

Instrument concepts should be TRL 5 or above at time of a potential spaceflight development contract award and must reach TRL 6 by PDR (see Section 1.3 for milestone date assumptions).

TRL is defined in NPR 7123.C Appendix E and Technology Readiness Assessment best practices are found in NASA Special Publication SP-20205003605.

3.7 Instrument Performance and Constraints

A complete list of performance and accommodation targets for the Polarimeter Instrument are provided in Attachment B.

The accommodation parameters are intended to be guidelines and any exceedances can be negotiated during study.

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4 WORK TO BE PERFORMED

4.1 Design Concept Development and Related Analyses

The Contractor shall develop an instrument design concept and perform associated engineering analyses to justify design parameters, tolerances, and design/performance margins. (CDRL’s 3-6, 8, 9)

The Contractor shall provide a quantitative comparison of the instrument performance against the performance and allocation targets outlined in Section 3.7. (CDRL’s 3-6, 8, 9)

The contractor shall provide an instrument Concept of Operations. This shall include nominal day-in-the-life operations, on-orbit calibrations and frequency, and any special activities

(diagnostic activities, on-orbit flight software loads, etc.) (CDRL-14)

The Contractor shall provide an initial analysis, and a state diagram, of the instruments ability to support engagement and disengagement of all cases/modes including, but not limited to, the following:

• Safe Mode – a thermally and optically safe configuration supported for an indefinite duration.

• Nominal Operations – Fully functional configuration employed for normal operations and data collection.

• Standby Mode – Configuration providing health and safety telemetry, but not collecting science data.

• Maneuver Mode – safe state for any spacecraft maneuvers (may be the same as a mode above).

(CDRL-14)

The Contractor shall identify ground science data processing required to create Level 1 science data products, including any assumptions, required inputs, etc. See https://www.earthdata.nasa.gov/engage/open-data-services-and-software/data-information-policy/data-levels for definitions of Level 1 data product. (CDRL-15)

The Contractor shall define a calibration methodology (both pre-launch and on-orbit) as applicable for the instrument. (CDRL-14 and -15)

The Contractor shall describe a reliability approach (selective redundancy, parts selection, etc.)

to meet the required lifetime and Risk Class C. (CDRL-17)

The Contractor shall identify single-point failures and fault critical elements. As part of this analysis the Contractor shall describe the fault tolerant/graceful degradation features of the design, as well as potential mitigations. (CDRL-17)

The Contractor shall develop a Master Equipment List (MEL), using the template that will be provided after contract start. The MEL shall document the mass, power, and TRL of each major component. (CDRL-10)

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The Contractor shall provide descriptions of any simulation and analytical tools (e.g., Instrument

Performance Model) used in the assessment of the design and/or performance, including heritage and validation of the tools. (CDRL-3-6, 8, 9, 19, 23)

The Contractor shall provide a CAD Model of the proposed instrument in all expected configurations (launch/stowed, deployed, etc.). (CDRL-16)

The Contractor shall provide a high-level recommendation for tailoring NASA standards listed in Section 2.2. The Project would like preliminary information regarding where the Contractor would propose following other standards or commercial practices in lieu of NASA standards.

This is a high-level assessment, not a formal compliance matrix. (CDRL-18)

The Contractor shall provide a compliance assessment of all requirements, including performance, functional, environmental and test, and mission assurance. (CDRL-19)

The Contractor shall provide any driving requirements impacting mission design (e.g. pointing control, knowledge, jitter, peak power, keep out zones, etc.). (CDRL-21)

The Contractor shall provide a Verification & Validation Plan, including but not limited to, significant test events, any testing deferred to higher levels of assembly, test facilities. (CDRL-

20)

The Contractor shall provide all parameters in the Instrument Performance and Accommodation

Spreadsheet provided after contract award. (CDRL-9)

4.2 Feasibility and Trade Studies

There following studies shall be performed by the Contractor:

1. The contractor shall conduct a trade study considering up to three alternate orbits and the impacts to instrument concepts and performance. The alternate orbits may require changes to orbit altitude or plane.

2. The contractor shall study and define pointing requirements, as well as different methods to achieve them should requirements be restrictive.

a. Includes pointing accuracy, knowledge, stability, and jitter.

b. Define constraints (e.g., relative placement of ACS sensors) that are required to meet requirements.

c. Define calibration methods, feasibility, and any required spacecraft functionality.

3. The contractor shall conduct a study to define the mechanical keep out zones and identify mitigations to aid in instrument accommodation.

4. The contractor shall Perform a trade study on the use of onboard lossless compression to reduce data rate/volume. Compression schemes considered should be realizable within instrument firmware or software resources. Determine the range of best, worst, and typical compression ratios. The contractor shall evaluate the impact to the concept design

(cost, schedule) for compression accommodation.

5. The contractor shall conduct studies to determine the feasibility, cost, and schedule impacts of potential performance enhancements or descopes to the Polarimeter. The study

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shall indicate when in the schedule the decision to take that enhancement or descope must be made. Potential performance enhancements or descopes include:

a. Descope from nadir view Full Width at Half Maximum (FWHM) resolution at the

Earth’s surface from 500m to 1km.

b. Options to simplify (descope) calibration components to reduce cost, risk or improve schedule.

c. A performance enhancement to add a channel in the Oxygen-A band absorption window, possibly with fewer view angles than other channels and at the expense of view angles from one of the other VIS channels.

d. A performance enhancement to ensure identical viewing geometries of the pair of spectral channels (in the NIR and SWIR) used to perform cloud property retrievals.

e. Identification of the feasibility of including a channel in the UV spectral range as specified in the performance target attachment.

The Contractor can propose additional/alternate trade or feasibility studies.

The contractor shall conduct a trade study to identify other descope options for the instrument, including estimated savings, risk reduction, and impact for each option identified.

4.3 Technology Readiness, Heritage, and Engineering Development

The contractor shall assess, justify, and report the technology readiness of all instrument subsystems and provide an associated technology maturation plan for all subsystem less than

TRL6. (CDRL-11 & -12)

The Contractor shall develop an Engineering Development Plan based on technical risks, that describes test plans and milestone schedule for appropriate Engineering Development Unit(s) or other prototypes and testing proposed by the Contractor. (CDRL-11)

The Contractor shall provide descriptions of the flight hardware and software heritage as well as any relevant differences between the claimed heritage and the proposed design (for example, on-orbit environment, mission duration, requirements, etc.). (CDRL-11)

4.4 Risk Reduction and Demonstration

Risk reduction and demonstration (RR&D) is sought for areas the Contractor identifies and proposes. Proposed RR&D efforts shall address one or more risks and/or demonstration of feasibility to meet performance targets, design margins, or other objective to improve confidence in the suitability of the instrument concept. Proposed efforts can include performance modeling, system design and analysis, as well as more complex laboratory demonstration. Laboratory demonstrations are intended to mitigate schedule risk of key subsystems that would benefit from additional development, analysis, modeling, proof-of-concept, breadboarding and/or testing to demonstrate a design concept or integration and test technique. (CDRL’s 33-38)

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4.5 Management, Cost and Schedule

The Contractor shall develop a flight implementation-phase schedule from award to flight hardware delivery based on proposed NRE (design and analysis), technology maturation and technical risks. The schedule shall show the following major instrument reviews: achievement of

TRL 6, SRR, PDR, CDR, TRRs, PER, and PSR. The schedule shall include phases for development of the instrument hardware and software performance models, physical model(s)

(e.g., prototypes, engineering development units, etc.), long-lead procurements, I&T, V&V activities, and the top three critical paths. (CDRL-28)

The contractor shall suggest estimated months for milestones that will minimize the overall cost and minimize the developmental risks. (CDRL-28)

The contractor shall provide a detailed MEL down to component level of assembly. NASA will use the provided MEL to produce independent cost estimates. A component, as defined in the

GEVS (GSFC-STD-7000) Section 1.8, is a functional subdivision of a subsystem and generally a self-contained combination of items performing a function necessary for the subsystem's operation. (CDRL-10)

The Contractor shall provide their own bottoms-up cost estimate for the full life cycle of the instrument from Contract Award through Phase D for the development and production of the flight instrument including required technology and engineering development required, qualification and engineering development models, any ground support equipment to be developed, flight software/FPGA development, flight spare hardware, etc. In addition, the cost shall include the cost of post-delivery support based on durations provided in section 1.3; that includes Observatory I&T support for integration of the instrument to the spacecraft and overall observatory environmental test as well as pre-launch support at launch site and post-launch commissioning plan. (CDRL-29)

The Contractor shall identify and rank risks to the development of the instrument and describe associated mitigations. The likelihood and criticality of risks will be ranked on a 5x5 matrix per

GPR 7120.4D. The Contractor shall identify alternate implementation paths for all high-risk items. (CDRL-30). In addition, the contractor shall provide an estimated cost and schedule impact associated with each risk per CDRL-30.

The contractor shall provide a flight-spare philosophy for proposed concept. The spare philosophy shall be appropriate to minimize delivery schedule impact created by failure, contamination or other plausible events. (CDRL-25)

The contractor shall provide long-lead item philosophy and long-lead list for proposed concept.

The long-lead philosophy should include post-pandemic effects on parts availability. (CDRL-26)

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5 PERFORMANCE PERIOD, DELIVERABLES, AND REPORTING

SCHEDULE

The overall concept study period will last six calendar months from contract award. The risk reduction activities can start anytime per vendor’s proposed plan and be completed by 15 months after contract award.

5.1 Reviews, Reporting, and Deliverables

The Contractor shall perform the reviews and reporting tasks and provide deliverable products as specified below.

The Contracting Officer's written determination that Government requests for action (RFA's) or requests for information (RFI's) regarding the deliverable reviews and products have been closed out will constitute acceptance of the deliverable.

5.2 Status Meetings and Reviews

5.2.1 Kickoff Meeting

The Contractor shall support a kickoff meeting within 2 weeks of the Authorization to proceed to provide a team introduction, summary of the proposed work for the study, proposed study schedule, and a high-level introduction to the initial instrument concept. (CDRL-3)

The Contractor shall deliver a soft copy of the Kickoff chart set 24 hours prior to the meeting. (CDRL-2)

The Kickoff meeting will be conducted virtually for 2-hours duration and will be setup by

Government.

5.2.2 Weekly Status Tag up

Weekly teleconferences will be scheduled to allow the Contractor to provide status, ask questions of clarification and to request additional information.

The weekly status meeting will be conducted virtually for 30-minutes duration and will be setup by Government. (CDRL-1)

5.2.3 Monthly Formal Status Review

Monthly in-person with the option for virtual meetings will be scheduled to allow the Contractor to provide status/progress of risk reduction activities, provide status of any procurement and detailed test results. The monthly status meeting will be conducted either in-person or virtually for 30-60 min duration and will be setup by Government. The contractor will provide all detailed status reports and progress in presentation package, 24-hour prior to the meeting. (CDRL-6)

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5.2.4 Check Point Reviews (CPRs)

The Contractor shall present a summary of the results of the work performed for the Check

Points Reviews. The first review will be held virtually; the second will be held at Vendor’s facility.The Contractor will plan on a half day up to a full day review for the each check points as described below. The Contractor will deliver a soft copy of the CPR chart set 72 hours prior to the review. (CDRL’s 4-5)

Below is the minimum expectation for each Check point relative to planned tasks:

1. Check Point 1 (award + 2 months), up to half-day duration:

• Requirements analysis (tasks described in section 4.1).

• Updated instrument concept (tasks described in section 4.1).

• Preliminary Instrument concept including instrument modes.

• Preliminary Block diagram.

• Preliminary TRL Assessment (tasks described in section 4.3).

• Updates on trade study results (tasks described in section 4.1).

• Initial trade study results (tasks described in section 4.1).

• Preliminary Spare philosophy (tasks described in section 4.3).

• Preliminary Long-Lead item definition (tasks described in section 4.3).

• Preliminary SWaP based on presented concept (tasks described in section 4.1).

• Preliminary CAD files for instrument concept (tasks described in section 4.1).

• Preliminary cost, schedule, and risk assessment (tasks described in section 4.5).

2. Check Point 2 (award + 4 months), up to full-day duration:

• Final instrument concept including the list of anticipated subcontractors.

• Final Instrument Performance assessment.

• Final Instrument concept including instrument modes.

• Final Block diagram.

• Final TRL Assessment (tasks described in section 4.3).

• Final heritage item assessments (tasks described in section 4.3).

• Final Long-lead item lists (tasks described in section 4.3).

• Final spare list (tasks described in section 4.3).

• Final CAD files for instrument concept (tasks described in section 4.1).

• Final results on trade study results (tasks described in section 4.1).

• Final Integration and Test Flow.

• Final Spacecraft interface requirement.

• Final cost, schedule, and risk assessment (tasks described in section 4.5).

• Final SWaP based on presented concept (tasks described in section 4.1).

5.2.5 Concept Study Final Report Package

Final Presentation Package and Report due electronically 20 business days after Check Point 2.

(CDRL-8)

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5.2.6 Risk Reduction and Demonstration Kickoff Meeting

The Contractor shall support a risk reduction kickoff meeting within the first 4 months after contract award. The kick-off meeting will be conducted at vendor’s facility. This review can be conducted with any of the Check Point reviews. The contractor shall provide:

- Description of risk reduction and demonstration activities.

- How and why the RR&D activities relate to instrument concept.

- Planned goals, objectives and milestones.

- Description of planned facilities and major procurements.

- Description of planned or expected analyses, development, test & verification.

- Expected outcomes and impacts.

(CDRL-32)

5.2.7 Bi-Weekly Informal Risk Reduction and Demonstration Status Meetings

Bi-Weekly in-person, with the option for virtual, meetings will be scheduled to allow the

Contractor to provide status/progress of risk reduction activities, any procurements, updates to the progress of tests, and a detailed status report. The Bi-weekly status meeting will be conducted either in-person or virtually for 30-60 min duration and will be setup by Government.

(CDRL-33)

5.2.8 Risk Reduction & Demonstration Progress Reports

The contractor shall provide risk reduction & demonstration progress reports at award + 7 months, award+9 Months, Award +11 months, Award +13 months and award +15 months. The reports can be provided a PowerPoint presentation or PDF. The reports shall provide the following information for each risk reduction activity to Government:

- Status of each risk reduction activity.

- Detailed design, analysis and/or test results.

- Problems encountered, solutions planned or implemented.

- Updates to risk and/or technical maturity assessments.

- Plans and expectation for next progress period.

(CDRL-34 and -37)

5.2.9 Final Risk Reduction & Demonstration Report

The final risk reduction & demonstration report shall include the following:

- Final status of all planned risk reduction and demonstration activities.

- Detailed design, analysis and/or test results.

- Problems encountered and solutions implemented.

- Final risk and technical maturity assessment.

- Open questions which arose during the activities.

- Technology development plan to reach TRL 6 by PDR.

(CDRL-38)

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The final report shall include all available information in electronic form, including block diagrams, model descriptions, analyses and results; and associated drawings, schematics, photographs, plots, and graphs as supporting documentation to the conclusions of the risk reduction and demonstration activities. (CDRL-38)

AOS Polarimeter Instrument Study SOW AOSP-POLAR-SOW-0007 Revision -

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5.3 Contract Data Requirement List (CDRL)

The contractor shall deliver the data products specified in the following table:

Table 3. Contract Data Requirement List

ID Deliverable Comments Deliverable Format

Schedule

CDRL-1 Weekly Status Meeting Status, issues, Q&A, etc. Briefing charts Weekly

CDRL-2 Concept Study Kickoff Meeting (Review and Initial Assessment)

Documentation of mutual agreement on needed Trade Studies or Special Studies

Briefing charts Purchase Order Award + 2 Weeks

CDRL-3 Preliminary Instrument Concept Presentation

Note: Presentation includes preliminary technical description of concept, open trades and actions that require to be analyzed throughout the study

Briefing charts + Spreadsheet

Kick-off

CDRL-4 Check Point# 1: Updated Instrument Concept Presentation

Presentation includes technical description, analysis/concept(s) results, special study results, etc.

Preliminary analysis of many technical CDRLs.

Briefing charts + Spreadsheet+

MS Project

Award + 2 months (Check Point#1)

CDRL-5 Check Point# 2: Updated Instrument Concept Presentation

Note: will require closure of all concept study CDRLs. Briefing charts + Spreadsheet+

Budget

MS Project

Award + 4 months (Check Point#2)

CDRL-6 Monthly Status Review Status of technical and programmatic progress, issues, Q&A, etc.

Briefing charts

Monthly

CDRL-7 Action Item list and updates Support status of actions from any informal and formal reviews

Status sheet Weekly/ Status

CDRL-8 Concept Study Final Report Detailed report capturing final concept based on analysis results

Report Award + 5 months

CDRL-9 Instrument Performance Parameter and Accommodation Spreadsheet

Complete all fields in Instrument Performance Parameter and Accommodation Spreadsheet provided after award

Spreadsheet CP#1: Preliminary CP#2: Final

CDRL-10 Master Equipment List (MEL) Document mass, power, and TRL of each major sub-component. Template will be provided by the Government

Spreadsheet CP#1: Preliminary CP#2: Final

AOS Polarimeter Instrument Study SOW AOSP-POLAR-SOW-0007 Revision -

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CDRL-11 TRL Assessment / Heritage Assessment / Engineering Development Plan

TRL Assessment per 7123.1 Appendix E or Best Practices Guide. Assessment of heritage and documenting deviations from heritage

Preliminary:

Briefing charts Final: Briefing charts / Report

CP#1: Preliminary CP#2: Final

CDRL-12 Technology Maturation Plan Outline a plan to reach TRL 6 by Mission PDR Preliminary:

Briefing charts Final: Briefing charts / Report

CP#1: Preliminary CP#2: Final

CDRL-13 EDU/ETU Philosophy & Plan Briefing charts Preliminary:

Briefing charts Final: Briefing chart / Report

CP#1: Preliminary CP#2: Final

CDRL-14 Instrument operational concept

Document instrument operational concept- including instrument mode diagram, calibrations, and day-in-the life on orbit

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-15 Level 1 Data Processing Document data processing required to create calibrated observable data products

Briefing charts

CDRL-16 CAD Model CAD Model for instrument. Provide any applicable configurations (e.g., launch/stowed, deployed, etc.)

STEP file CP#1: Preliminary CP#2: Final

CDRL-17 Risk Classification Assessment Assessment per NPR 8705.4, Appendix D for Mission Class C, including identification of Single Point Failures

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-18 NASA Standards Tailoring for

GSFC-STD-1000G, GSFC-STD-

7000A Rev B, etc.

Recommendations on tailoring of NASA standards that are provided as reference. Project would like to know where the Contractor would propose other standards or commercial practices in lieu of NASA standards or request waiver. High level assessment, not a formal compliance matrix

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-19 Requirements Compliance Assessment

Matrix Spreadsheet CP#1: Preliminary CP#2: Final

CDRL-20 Verification & Validation Plan Document or Briefing Charts

CP#1: Preliminary CP#2: Final

CDRL-21 Identification of Driving Requirements

Identify driving requirements that impact the system (pointing, keep out zones, jitter, etc.)

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-22 Sensitivity to Orbit Parameters Study

Study impacts to instrument design/performance for up to 3 different orbits adjusted in altitude or plane.

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-23 Performance, Risk, and Cost Trade Study

Trade performance parameters, Rick classification, cost, etc.

to meet mission needs

Briefing charts CP#1: Preliminary

AOS Polarimeter Instrument Study SOW AOSP-POLAR-SOW-0007 Revision -

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CDRL-24 Trade study Report Status of analysis supporting trade studies described in section 4.2

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-25 Spare parts philosophy and list Briefing charts Briefing charts CP#1: Preliminary CP#2: Final

CDRL-26 Long Lead Item List List of long-Lead items for flight procurement of one flight hardware plus any spare based on vendor’s proposed spare philosophy

Spreadsheet CP#1: Preliminary CP#2: Final

CDRL-27 Flight Implementation schedule

Flight development schedule based on Instrument concept MS Project

CP#1: Preliminary

CDRL-28 Flight cost estimate Cost of one flight hardware plus any engineering development units, and spares.

Spreadsheet CP#1: Preliminary CP#2: Final

CDRL-29 Risk assessment List of proposed risks against the Instrument concept along with the proposed mitigation plan

Briefing charts CP#1: Preliminary CP#2: Final

CDRL-30 Instrument block diagram block diagram showing each subsystem-to-subsystem functional flow

Briefing charts or Drawing

Preliminary: CP#1 Final: CPT#2

CDRL-31 List of proposed flight spare units/parts

List of flight spares and assembly level Briefing charts Spreadsheet

Preliminary: CP#1 Final: CPT#2

CDRL-32 RR&D Kickoff Meeting RR&D kick off meeting briefing Briefing Charts On or before CP#2

CDRL-33 RR&D Status Meetings Bi-weekly informal report briefing charts Briefing Charts Monthly after RR&D Kickoff

CDRL-34 RR&D Progress Report #1 Report on progress to date Report or Briefing Charts

Award + 7 months

CDRL-35 RR&D Progress Report #2 Report on progress to date Report or Briefing Charts

Award + 9 months

CDRL-36 RR&D Progress Report #3 Report on progress to date Report or Briefing Charts

Award + 11 months

CDRL-37 RR&D Progress Report #4 Report on progress to date Report or Briefing Charts

Award + 13 months

CDRL-38 RR&D Final Report Detailed report on all progress made during RR&D effort Report Award + 15 months

CDRL-39 RR&D Supporting Documentation

Electronic files supporting RR&D conclusions Electronic files Award + 15 months

AOS Polarimeter Instrument Study SOW AOSP-POLAR-SOW-0007 Revision -

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6 ABBREVIATIONS AND ACRONYMS

Abbreviations/

Acronyms Definition

AOS Atmosphere Observing System

CCB Configuration Control Board

CDR Critical Design Review

CCP Clouds, Convection, and Precipitation

CCSD Consultative Committee on Space Data Systems

DO Designated Observables

DS Decadal Survey

GSFC Goddard Space Flight Center

ESO Earth System Observatory

FOV Field of View

ITAR International Trade in Arms Regulation

KOZ Keep Out Zone

LEO Low Earth Orbit

MEL Master Equipment List

NRE Non-Recurring Engineering

PDR Preliminary Design Review

PER Pre-Environmental Review

PSR Pre-Ship Review

RR&D Risk Reduction and Demonstration

SBU Sensetive But Unclassified

SSR System Readiness Review

TBD To be determined

TRL Technology Readiness Level

TRR Test Readiness Review

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7 ATTACHMENT B

Attachment B Atmosphere Observing System-Polar Polarimeter Performance Targets and

Technical Resource Allocations

These performances are written as targets, with minimums indicated in brackets. The AOS-P multi-angle polarimeter shall measure radiance and degree of linear polarization (DoLP) in every channel and view angle. Nadir-view spatial Full Width at Half Maximum (FWHM) resolution at the Earth’s surface shall be no coarser than 500m [1 km]. Off nadir FWHM resolution shall not be coarser than r ⁄ cosθ , where r is the nadir FWHM resolution and θ is the view zenith angle at the surface. Measurements shall be made in a continuous daytime cross-track swath not less than

300 km [100km] wide. The along-track, center swath, multiple viewing angle range shall be at least ±57 at spacecraft.

The…