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SCIENCE MISSION DIRECTORATE POLICY

Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA) 

Secondary Payloads Rideshare

SMD Policy Document SPD-32 

December 1, 2020

Responsible SMD Official: Deputy Associate Administrator for Programs (DAAP)

VERSION HISTORY

Original SPD-32 October 23, 2018

SPD-32 Rev 1 October 4, 2019

DISTRIBUTION STATEMENT: Approved for public release.
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I. BACKGROUND

This policy establishes the Science Mission Directorate (SMD) framework for utilizing the excess 

capacity, to include excess ascent performance and other mission resources on SMD missions by 

supporting the integration of secondary payloads onto Evolved Expendable Launch Vehicle 

(EELV) Secondary Payload Adapter (ESPA) rings. In this document, the term “ESPA-ring” will be 

used to represent all variants of the Evolved Expendable Launch Vehicle (EELV) Secondary 

Payload Adapter (SPA) ring, including the standard ESPA, the ESPA Grande, and propulsive ESPA. 

This policy enables increased opportunities for launch accommodations for ESPA-class payloads 

that address various science, technology, and exploration goals. Additionally, the process for 

identifying, prioritizing and selecting secondary payloads in accordance with this policy, is captured 

in Appendix C of this document.

II. POLICY

a. It is SMD policy to enable rideshare or launch accommodation opportunities using an ESPA 

ring as part of the launch service procured for an SMD primary payload.

b. SMD will determine the potential for excess capacity, as identified by Launch Services Program

(LSP), after selection of the primary payload (once launch requirements are known). If excess 

capacity is identified, SMD will utilize the identified excess capacity on SMD primary payload 

missions using an ESPA ring, for the launch of SMD-sponsored secondary payloads, either 

competed or directed, that meet science, technology, and exploration goals.

c. SMD may solicit science, technology, and exploration investigations as secondary payloads 

through Announcements of Opportunity or the ROSES NASA ResearchAnnouncements.

d. SMD may offer any excess capacity not utilized for SMD investigations to other NASA Mission 

Directorates (MD), to other U.S. Government Agencies, or to NASA’s International Space 

Agency partners in accordance with international agreements for international collaborative 

efforts relating to science, technology, and exploration goals.

III. APPLICABILITY

a. This policy is applicable to the Science Mission Directorate.

b. This policy also applies to:

(1) all orbital commercial launch services procured for SMD-sponsored primary payloads;

(2) orbital commercial launch services procured for other Government Agencies;

i. for which NASA SMD is responsible and
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ii. the other Government Agency lacks secondary payload candidates to utilize all 

excess capacity.

(3) orbital commercial launch services procured for other International Space Agency 

partners for which NASA SMD is responsible to provide;

c. This policy is not applicable to launches of non-SMD primary missions, sub-orbital launches, or 

payloads launched on the HEOMD Space Launch System (SLS).

d. In this policy document, all mandatory actions (i.e., requirements) are denoted by statements 

containing the term "shall." The terms "may" or "can" denote discretionary privilege or 

permission; "should" denotes a good practice and is recommended, but not required; "will" 

denotes expected outcome; and "are/is" denotes descriptive material.

e. In this policy document, all document citationsare assumed to be the latest version unless 

otherwise noted.

IV. AUTHORITY

a. National Aeronautics and Space Act, 51 U.S.C. 20101 et seq.

V. REFERENCES

a. NPR 7120.5 NASA Space Flight Program and Project Management Requirements

b. NPR 7120.8 NASA Research and Technology Program and Project Management Requirements

c. NPD 8610.7 Launch Services Risk Mitigation Policy for NASA-Owned and/or NASASponsored Payloads/Missions

d. NPR 8705.4 Risk Classification for NASA Payloads

e. Charter of the NASA Small Spacecraft Coordination Group (SSCG)

f. NC 1000.15 Expendable Launch Vehicle (ELV) Flight Planning Board (FPB) Charter

VI. RESPONSIBILITY

a. The Deputy Associate Administrator for Flight Programs (DAAP) as delegated by the Associate 

Administrator for SMD shall:

(1) Ensure SMD compliance with this policy document.

(2) Determine the potential for excess capacity after selection of the primary payload in cooperation 

with LSP.
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(3) Oversee the process of offering secondary capacity on SMD missions to support science, 

technology and exploration investigations by NASA payloads from other Mission Directorates, 

other U.S. Government Agencies, and NASA’s International Space Agency partners.

(4) Oversee the evaluation and prioritization of secondary payloads, consistent with thispolicy.

(5) Finalize the prioritization of the secondary payloads, if needed, through a SMD Program 

Management Council or out of board process, and communicate the outcome to the FPB.

b. Each SMD Science Division shall:

(1) Allocate within their budget the funding to procure ESPA Integration Services (ESPA-IS) and 

Launch Vehicle Integration Services, as defined in Appendix C, Section 5, of this policy. The 

budget for these items will be maintained outside of the budget for the SMD primary or 

secondary mission, so as to minimize the effect of this policy on the lifecycle cost of the primary 

and secondary missions.

(2) The budget for the ESPA and LV integration services on SMD launches will besupported 

within the budget of the sponsoring Primary Mission Division.

(3) Request via email that the DAAP include an option for ESPA-class secondary launch 

accommodations in LSO request for appropriate solicitations of primary mission launch 

services.

(4) In cooperation with LSP, provide a catalog of rideshare capabilities and rideshare carrier options 

with relevant payload parameters for relevant and applicable solicitation calls. This information 

will be made available on the Science Office of Mission Assessment and Small Spacecraft 

Systems Virtual Institute (S3VI) websites.

c. Each SMD Science Division may:

(1) For SMD-procured secondary payloads, allocate costs within Announcement of Opportunity or 

ROSES NASA Research Announcement cost caps for ESPA Integration and Launch Vehicle 

Integration Services for non-SMD primary launch opportunities, if appropriate, since at the time 

of an Announcement release, the specific launch opportunity (SMD or non-SMD) will not have 

been identified.

d. The Small Spacecraft Coordination Group (SSCG) shall:

(1) Identify and maintain a list of potential ESPA-class payloads seeking launches, including payload 

candidates from NASA and other U.S. Government Agencies, on a best effort basis.
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(2) Operate a website through the S3VI that consolidates and shares public information on ESPAclass launch accommodation opportunities and capabilities. (https://www.nasa.gov/smallsatinstitute).

(3) Maintain a repository for a NASA-specific rideshare user's guide, approved launch/rideshare 

forecasts and rideshare/small satellite points of contact. (Note that per the SSCG Charter, the 

FPB will ensure existing applicable NASA policies are appropriately applied for launch service 

procurement and launch risk management, and that NASA acts in a coordinated and consistent 

manner regarding rideshare / secondary payload opportunities).

e. The Launch Service Program shall:

(1) Include the integrated ESPA ring requirements in the launch vehicle procurementdocuments, 

when appropriate.

(2) Develop solicitation-specific catalog of rideshare capabilities and rideshare carrier options with 

relevant payload parameters for applicable solicitation calls.

(3) Identify launch rideshare accommodation opportunities for NASA missions, in conjunction with 

the primary mission and the Launch Vehicle Contractor and provide this information to the 

S3VI, as representatives on the SSCG.

f. The Secondary Payload Provider shall:

(1) Include all costs associated with payload development, modeling, assembly, and integration and 

testing in their budget. This includes the delivery of all relevant interface documents, and travel 

to support all phases of secondary payload integration onto the ESPA ring, and the populated 

ESPA ring onto the LV.

(2) If consistent with the NASA solicitation, ensure that the cost of ESPA Integration and Launch 

Vehicle Integration Services for non-SMD primary launch opportunities is included in their 

mission budget.

(3) Include all costs associated with launch delays, including secondary payload storage and 

workforce costs, within their mission budget.

(4) Include mission unique costs, such as an independent Secondary Payload Processing Facility 

costs, within their mission budget. Standard ESPA Integration Services (ESPA-IS) and Launch 

Vehicle Integration Services are defined in Appendix C, Section 5, of this policy.
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VII. MEASUREMENT/VERIFICATION

a. Compliance with this document is verified by documenting viable rideshare options in 

prioritized order in an SMD Decision Memo (DM) and in FPB minutes documenting manifest 

decisions for applicable launches.
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Date: 2020.12.22 19:55:03 -05'00'

SIGNATURE BLOCK

Concurred by:

Wanda Peters, Ph.D. Date

Deputy Associate Administrator for Programs 

Science Mission Directorate

Approved by:

Thomas Zurbuchen, Ph.D. Date 

Associate Administrator

Science Mission Directorate
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BLANK PAGE
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APPENDIX A: ACRONYMS

CLA Coupled Loads Analysis

CM Centimeters

DAAP Deputy Associate Administrator for Programs 

DAAR Deputy Associate Administrator for Research 

DM Decision Memorandum

DPMC Directorate Program Management Council 

EELV Evolved Expendable Launch Vehicle 

ESPA EELV Secondary Payload Adapter

FPB Flight Planning Board

KDP Key Decision Point

KGS Kilograms

LBM Pounds mass

LRD Launch Readiness Date

LSP Launch Services Program

LSTO Launch Service Task Order

LV Launch Vehicle

MD Mission Directorate

NASA National Aeronautics and Space Administration 

NC NASA Charter

NPD NASA Policy Directive

NPR NASA Procedural Requirements

SLS Space Launch System

SMD Science Mission Directorate

SOMA Science Office of Management Assessment 

SSCG Small Spacecraft Coordination Group 

S3VI Small Spacecraft Systems Virtual Institute

APPENDIX B: DEFINTIONS

ESPA ring - A payload adapter for small-class secondary payloads on medium and 

intermediate/heavy class launch vehicles.

Standard ESPA ring - A payload adaptor that holds up to six secondary accommodations, not to 

exceed 710 pound-mass (lbm) or 322 kilograms (kgs) each.

ESPA Grande – An ESPA ring that holds up to four or five secondary accommodations, each with 

a mass of up to 1026 lbm or 465 kgs.

ESPA-class payload – a free-flying payload that attaches to any variant of an ESPA ring.
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Excess capacity - For the purposes of this document, excess capacity means excess ascent 

performance and other mission resources that would allow secondary payload opportunities.

Integrator - The Integrator is responsible for the management, development, integration, test, and 

delivery of the integrated ESPA flight system.

NASA payload - A payload developed by a NASA Mission Directorate or office, either in-house or 

under contract.

SMD-sponsored payload - A payload provided by a non-NASA entity under formal agreement with 

SMD (e.g., international cooperative payloads, OGA payloads).

Payload - A specific complement of instruments, sensors, equipment, and support hardware carried 

into space to accomplish a mission or a discrete activity in outer space. Specific characteristics: 

Personnel are not considered a payload nor a part of a payload.

Primary payload - A payload for which a launch vehicle is procured. Specific characteristics: A 

primary payload typically defines the orbital placement/trajectory, flight design, critical path of the 

mission integration including launch preparation process, and mission operations. The primary 

payload’s organization funds the launch service.

Secondary payload - A payload that is manifested subordinate to a primary payload and, therefore, is 

subordinate in launch date and orbit selection. Specific characteristics: A single secondary payload 

does not justify a dedicated launch. A secondary payload is usually independent of the primary 

payload, providing its own power and communication system, but is dependent on a primary 

payload’s launch vehicle to achieve orbit/desired trajectory. A secondary payload does not drive the 

launch mission’s orbit selection, flight design, or mission integration critical path without agreement 

from the primary payload. The secondary payload does not cause a launch delay without agreement 

from the primary payload. The secondary payload must have available an appropriate fidelity mass 

simulator to meet the schedule needs of the primary payload should the secondary be unable to 

support the launch date. There can be more than one secondary payload on a launch.

Small Spacecraft Coordination Group – A NASA group that provides cross-agency coordination for 

small spacecraft missions.

APPENDIX C: SMD RIDESHARE PROCESS

1. SOLICITATIONS

For applicable solicitation calls, SMD will include the following: a catalog of rideshare capabilities 

and rideshare carrier options with relevant payload parameters that will be available on the Science 

Office of Mission Assessments (SOMA) and S3VI websites. All rideshare-referenced 

documentation for inclusion in the solicitation will be approved by the SMD Deputy Associate
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Administrator for Research (DAAR) and filed in the solicitation program library at the SOMA 

website at https://soma.larc.nasa.gov/ and solicitation language will be included in the standard 

solicitation templates.

2. FACTORS FOR CONSIDERATION OF SECONDARYPAYLOADS

For secondary payloads seeking rideshare launch accommodations and that are not part of the 

solicitation process, the following are factors for consideration of potential candidates:

a. Spacecraft readiness and schedule alignment to the primary mission;

b. Suitability and compatibility of the secondary payload deployment parameters to the primary 

mission;

c. An ability to support and contribute to NASA’s science, exploration, or technology development 

objectives.

3. PRIORITIZATION PROCESS FOR SECONDARY PAYLOADS

Secondary payloads will be considered from the following offices, organizations, or entities in 

priority order:

a. SMD Division responsible for the primary payload, including the SMD Division responsible for 

reimbursable programs;

b. Other SMD Divisions

c. Other NASA Mission Directorates

d. Other Government Agencies not represented by SMD Divisions

e. International Space Agency Partners in accordance with international agreements for 

international collaborative efforts relating to science, technology, and exploration. International 

Agreements will be coordinated through NASA Office of Interagency and International 

Relations.

Due to LV processing timelines, the secondary manifest will be decided no later than 24 months 

prior to the launch date.

In situations where SMD is representing another Federal Agency using reimbursable funds to 

procure a launch service in support of a reimbursable primary mission, the sponsoring agency will be 

given the first opportunity to identify rideshare secondary payloads. If the funding agency does not 

identify internal or partner payload candidates to utilize all available excess capacity, SMD, by launch
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minus 24 months, will use the process outlined below for identifying potential rideshare 

opportunities. SMD will coordinate with the funding agency to perform accommodation studies of 

any SMD proposed secondary payloads to establish compatibility with the primary mission and to 

identify any impact on launch service costs that would be driven by the SMD-proposed secondary 

payloads. Once this evaluation is complete, the funding Agency retains the right to decide whether 

SMD-proposed rideshare payloads will be manifested. The participating agencies will determine the 

distribution of rideshare costs based on applicable law. A more detailed prioritization process for 

rideshare accommodations on reimbursable programs will be covered separately to this policy.

4. SELECTION PROCESS FOR SECONDARY PAYLOADS

The following describes the decision process for determining how the selection of candidate 

secondary payloads for launch accommodations on SMD primary missions will be determined.

1. When a primary mission is initiated, a rideshare capability will be incorporated unless technically 

infeasible. As the mission matures, the potential excess capacity will be refined, as necessary. 

During this process, the rideshare options will mature and the NASA rideshare database will be 

updated regularly, at a minimum at major key decision points.

2. After the Launch Service Task Order is awarded by LSP, when the specific launch service for 

the primary mission is identified, a high-fidelity mission design analysis will be conducted to 

determine precise excess performance. At that point, the secondary accommodation (e.g., ESPA 

on or off) will be formalized at the FPB. If it is not clear whether a rideshare capability can be 

provided, the SMD division sponsoring the primary mission makes the final determination, 

which will be documented in FPB minutes. If the primary mission uses all launch capability and 

there is no excess capacity available, then no ESPA ring will be flown.

3. If there is excess capacity, the SMD Division sponsoring the primary mission determines if this 

excess capacity can be used internally to that Division.

4. If the Division sponsoring the primary payload cannot use all excess capacity, the DAAP 

conducts a poll of other SMD Divisions and technology offices to determine if the excess 

launch vehicle capability can be used within SMD.

5. If Divisions submit more candidates than available slots, then a special DPMC will be held to 

prioritize SMD secondary candidates. The factors and considerations for prioritizing secondary 

payloads amongst Divisions are (a) national importance; (b) relevance to SMD science, 

technology, and exploration goals; (c) other launch opportunities; (d) secondary payload 

readiness; (e) schedule alignment with the primary payload Launch Readiness Date (LRD); (f) 

risk to the primary payload; (g) launch constraints; (f) orbit compatibility to primary mission; (g) 

Agency priorities; (h) SMD partner priorities. This is not a prioritized list.

6. The decision will be documented in a Decision Memo.
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7. If, after SMD Divisions are polled, there is remaining excess capacity, then other NASA Mission 

Directorates are polled by the DAAP to determine if this capacity can be used within NASA. 

Identified payloads will be prioritized according to agency priorities.

8. The SSCG will then be notified that excess capacity is available and will assist SMD, based on its 

current NASA and other U.S. Government Agency payload candidate list. The SSCG may have

access to additional data from other sources about potential secondary candidates that could be 

utilized, with the following priority:

a. Other Government Agencies not represented by SMD Divisions;

b. International Space Agency Partners in accordance with international agreements.

9. After all candidate secondary payloads are identified, LSP will assess compatibility of the 

candidates with the launch performance and primary mission orbit. Additionally, the integration 

services organization will assess whether the designs of the secondary candidates would be 

compliant with the “Do No Harm” requirements. Using these assessment results, a special 

DPMC will be held to prioritize and select the secondary payloads. All decisions involving SMD 

missions will be documented in a SMD Decision Memo or other agreement document.

10. The FPB will provide final approval and will manifest the secondary payloads using the FPB 

process.

11. A list of potential back-up payloads for each NASA rideshare opportunity will be maintained by 

the LSP. LSP will assess compatibility with the applicable mission and provide constraints and 

replacement costs based on timing with respect to launch. If a secondary payload fails to meet 

required milestones or requirements, depending on where the mission is within the integration 

process, it may be replaced with an alternate secondary payload from the back-up list or be 

replaced with a mass simulator, with SMD and FPB approval.

12. Once a secondary is selected as part of the final manifest, the secondary payload providers will 

be notified.

5. DEFINITION OF ESPA INTEGRATION SERVICES (ESPA-IS) AND LAUNCH 

VEHICLE (LV) INTEGRATION SERVICES

The following describes ESPA Integration Services (ESPA-IS) and Launch Vehicle (LV) integration 

services that the primary payload sponsoring Division shall pay for.

1. ESPA-IS includes all procurement, integration, and analysis associated with the integration of 

secondary payloads onto an ESPA ring. This includes:

1. ESPA Integrator contract fees;

2. Physical integration of secondary payloads onto an ESPA ring;
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3. All interface control documents, modeling, testing, and analysis of the integrated system;

4. All procurement costs, including procurement of the ESPA ring and all ancillary hardware, 

such as: separation systems, mass simulators for the secondary payloads, and all associated 

harnessing.

2. LV Integration includes integration of the populated ESPA ring onto the launch vehicle, and all 

associated modeling, testing, and analysis. This includes:

1. Physical integration of populated ESPA ring onto LV;

2. All LV analyses (thermal, coupled loads, trajectory, electrical, EMI/RFI, etc.);

3. “Communal’ T-0 purge for secondary payloads

4. Shared secondary Payload Processing Facility for the complement of rideshare payloads