Attachment1_MaGMA_SOW_20260610.docx

Mathematical Gravity Modeling Advancement

Statement of Work

Geosciences Division, Office of Geomatics

June 10, 2026

Table of Contents

UNCLASSIFIED

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Background and Scope The National Geospatial-Intelligence Agency (NGA) is a key member of the National System for Geospatial Intelligence (NSG) that supports U.S. strategic technology foundational to the Nation's Department of Defense (DoD), Department of Homeland Security, and the Intelligence Community.

NGA’s Office of Geomatics’ (SFN) is required to design geodetic models, and to provide geodetic error analysis support to its diverse group of military and civilian customers. NGA creates the Earth Gravitational Model (EGM) for use in navigation products for the DoD and for general use by industry and academia.

Recently, NGA conducted a review of the mathematics behind EGM. This review showed improvements can be made to the modeling process to increase the EGM’s accuracy, with additional downstream benefits to Inertial Navigation System (INS)-based gravity products supplied to DoD customers. NGA is seeking to update the EGM through the use of modernized, computational environments to apply new mathematical techniques and algorithms.

NGA is seeking a vendor capable of reviewing current methodologies and developing new, optimized mathematical techniques to apply to EGM and the existing novel gravity simulator codebase (NGSC) which will be provided by NGA. Furthermore, the methods developed will be able to generate an EGM or general gravitational model that will produce gravimetric quantities (e.g. point gravity anomalies, mean gravity anomalies, geoid heights, deflections of the vertical, etc.) valid at the topographic surface with performance similar to EGM2008.

Requirements Modeling The vendor shall develop more realistic planetary models based on previous work provided by NGA. These models will be composed of layers, mass elements, and triangulations that allow for spatial and radial density variations. Furthermore, the planetary models will incorporate these components in such a way that they allow for finer resolution in regions of interest (i.e. irregular triangulations and inhomogeneous mass element distributions). While at least one of these models will be a model of the Earth the others may be fictitious planets for testing/research purposes and/or other planetary bodies of interest (e.g. the Moon and Bennu). Derived gravimetric quantities from the application of the NGSC to these models will be compared to other suitable modelling techniques (e.g. RTM, EGM08, etc.) or other data as available as a validation method for both the NGSC and models.

The vendor shall implement and improve analytic continuation code; NGA will provide the code this is to be based off. This will be done by integrating the provided code into the main NGSC and developing and testing new methods for analytic continuation. All analytic continuation code will be evaluated to determine the applicability of parallel computation techniques in preparation for operational use.

The vendor shall develop and explore the theoretical basis for new computational approaches to estimating the spherical harmonic expansion (SHE) model coefficients. This will involve “out-of-core” inverse techniques, such as stochastic gradient descent (SGD) based on mini-batches, which will lower the memory use associated with typical large scale matrix inversion. Furthermore, the vendor will also explore other methods to obtain the SHE model coefficients from forward modelling procedures.

The vendor may conduct reviews of potential new avenues of research or development aligned with the previous topics and shall work with NGA Subject Matter Experts (SMEs) and the Principal Investigator (PI) to evaluate whether new techniques, methods, or algorithms will provide benefit to NGA. Approval from the PI is required for significant changes in resources or time applied to the development of the overall deliverables.

Technical A successful proposal shall demonstrate that the vendor has the staff with the appropriate experience in geodesy and geophysics, specifically in relation to gravitational field modeling, theoretical and applied mathematical methods to model gravity, and knowledge of modern software development.

The vendor shall work with NGA PI to understand and develop a plan to incorporate code into NGA’s current compute infrastructure, develop codebases according to NGA security requirements, and incorporate best practices into software development that comply with secure software development practices based on National Institute of Standards and Technology (NIST) guidance. The vendor will work through NGA PI to ensure that delivered software adheres to NGA software security and cybersecurity policies as applicable, and NGA will make the final determination related to software security and cybersecurity concerns. These determinations by NGA cannot be appealed by the vendor.

The vendor shall improve the NGSC either through coding updates or inclusion of new novel methods if they prove to be better. The former can be accomplished by continuing to explore and mitigate the use of high numerical precision, examining and improving the use of parallel computation techniques (i.e. multi-threaded, multi-processing, and GPUs), and updating methods and adding features based on new mathematical understanding. For the latter the offeror will need to demonstrate that the novel approach is better and then have written approval from the NGA PI or Contracting Officer Representative (COR).

The vendor shall work with NGA PI to ensure developmental code and production code are delivered in a format usable by NGA. Developmental code (code used for testing and exploratory analysis) may be delivered in various languages (e.g. Julia, Mathematica, etc.) which are subject to NGA PI agreement and shall be delivered on a rolling release or ad hoc cycle (minimum quarterly) to help track progress. Production code (code used to directly support the NGSC) shall be in Python. However, if the vendor can show that better performance can be gained using another coding language, prior to implementing production code in that other language, the offeror shall receive express written approval from the NGA PI or COR.

Deliverables A projected timeline for completion of milestones and tasks to be used as a reference. This should consist of both a rough timeline for the completion of the full project and a more detailed timeline for the current year.

Fully documented code, code paired with comprehensive written explanations detailing how, what, and why, hosted in a repository approved by NGA’s SME, including:

Codebase Additional features added to the NGSC include research methods used in the development code and vetted features in the production code Any codebase developed or used to demonstrate results to NGA whether or not the method proved viable Any codebase used for training purposes White papers or other documentation that outlines the process behind all model creation, technique development, or improvement over current NGA procedures as determined by NGA PI. This should include:

A clear and concise description, discussion flowchart, or other easily understood explanation of the ability to compute gravimetric quantities of interest at point locations from starting data including how NGA data will be used in the process.

A discussion of how the final deliverable product is envisioned to look and the manner in which the final product shall be used.

Methods tested but determined not viable Including a presentation or documentation on tests and results Training sessions in the form of virtual or in person workshop sessions when determined needed by NGA PI. Training sessions can be ad hoc or be developed for future, unlimited use by NGA and the US Government.

Models and data developed during the course of this project:

Planetary model information (e.g. triangulation parameters, planetary density data, etc.)

Taylor series and Spherical Harmonic Series coefficients (out to degree and order 2,700 for Earth models). The Earth SHE model will establish a baseline of performance to be measured against EGM2008 performance (methods such as dynamic ocean topography, geoid height point comparisons, etc. will be considered and discussed at the kick-off meeting).

Performance Requirements Summary

Standards Acceptable Quality Levels

Reports and Meetings Communication between NGA and the vendor is essential to achieving success in meeting our mission, conducting business, and advancing our abilities to deliver for our customers.

The vendor and NGA will hold a kick-off meeting to set expectations, goals, scope, baseline performance criterion and determine an initial timeline.

The vendor will hold a weekly technical exchange/update meeting with NGA PI and others as deemed necessary by NGA.

NGA and the vendor shall conduct quarterly technical exchanges meetings virtually or in-person to outline the progress of the vendor’s work. These will include technical reports, white papers, or any other form or correspondence from the vendor on project status.

Monthly Status Reports The vendor shall deliver a monthly status report. The monthly status report shall include actions taken, progress made, and any issues encountered. The monthly status report shall be delivered via email to NGA Program Managers, Mission Managers and the COR on the last business day of each month.

Security This work is unclassified, uncleared contractor personnel are authorized to work on this contract.

Foreign nationals are not permitted to perform unclassified work under the terms of this contract without prior written approval from the Contracting Officer (CO) or the COR. Should NGA identify the use of unauthorized personnel, the CO may direct the vendor, at its own expense, to remove and replace any unauthorized contractors, subcontractors, or other personnel performing on the contract. Such action may be taken at the NGA's discretion without prejudice to its rights under any other contract provision, e.g., termination for default.

All contractor personnel performing the technical work, and for visiting NGA facilities shall follow all applicable NGA, Intelligence Community (IC), and DoD information security and operational security policies and guidance during performance of contract requirements. Some of the work may require higher clearance levels later in the contract. NGA is the sole determiner of classification level and will decide whether or not a security clearance is necessary and whether foreign nationals can be permitted to work on a project. The vendor shall not publish or present any findings, results, or progress on work from this project to audiences outside of NGA and vendor organization without express written approval from NGA.

Data Security All data secured through this contract is to be kept at the Unclassified level.

Information pertaining to this contract shall not be released to the public unless authorized by the CO.

Data Ownership Government-furnished information (GFI) remains the property of the Government. The Contractor shall use GFI only for performance of this contract and shall be responsible for its proper protection and return.

All data, including raw data, processed data, reports, and other documents generated, acquired, or produced by the Contractor in the performance of this Contract, shall be considered Government-owned information.

The Government shall have unrestricted rights to use, disclose, reproduce, or publish any such data. Upon completion or termination of this contract, the Contractor shall deliver all such information to the COR or destroy it, if so directed All data acquired with this contract will have no less than Government purpose rights in accordance with the definition in DFARS 227.7101. The deliverable data, the databases, all database content, and finished products created by the vendor shall have government purpose rights for a five-year period that shall commence upon execution of the contract. Upon the expiration of the five-year period, the Government shall have unlimited rights to the technical data.

Quality Assurance The vendor is responsible for product/service quality as it pertains to all requirements under this statement of work (SOW). The vendor shall take all steps necessary to ensure that the content meets all quality and specification aspects required by NGA and its customers. All vulnerabilities identified by either the vendor or NGA shall be remediated in a timely manner, but within 60 days of discovery or disclosure.

Period of Performance The overall Period of Performance, inclusive of options, is three (3) years, comprising of one (1) Base Year and two (2) Option Years.

Travel The vendor shall travel to NGA St. Louis and other facilities as needed to accomplish its tasks. Travel must be approved by the COR in advance of all trips. Travel not approved in advance will not be reimbursed by NGA. Travel will be provided on a Cost Reimbursement no fee basis and converted to a firm fixed price at the end of each 12-month POP.

Invoicing The vendor shall submit monthly invoices to the Invoice Processing Platform (IPP) website, https://www.ipp.gov/, based on the non-travel total. Approved travel expenses will be added to the monthly invoice as incurred.

Contracting Officer Representative (COR) The COR will serve as the Government’s primary point of contact for all technical matters and deliverable acceptance.

Lauren Sandidge 314-676-5729 Lauren.N.Sandidge@nga.mil image1.png