SSEP Mission 19 to ISS: Critical Timeline

Information added or updated since this page went live on February 26, 2024, is in GREEN TEXT below.
Information still to be determined (if any) is in RED TEXT below.
Dates and times that are subject to change at NASA’s discretion are in PURPLE TEXT below.

Last update of this page: February 26, 2024, 3:15 pm ET


Below is a timeline of milestones for SSEP Mission 19 to the International Space Station (ISS). It covers activities associated with how communities join the program, the experiment design competition, selection of flight experiments, launch, operations aboard ISS, and mini-laboratory return to Earth. The timeline is broken into 2 phases: 1) the Experiments Design Phase which concludes with the selection of the flight experiment for each participating community, and 2) the Flight Operations Phase, which concludes with the flown experiments returned to the communities for student team harvesting and analysis.

A Note about the ferry flights to and from the ISS. The current plan for transporting the SSEP Mission 19 experiments payload to and from ISS is a SpaceX Commercial Resupply Services (CRS) mission expected to launch from NASA’s Kennedy Space Center, FL, in Spring/Summer 2025. The typical duration on orbit is 4-6 weeks. This page therefore includes only general target dates for milestones associated with the Flight Operations Phase in Spring/Summer 2025.

Phase 1: Experiment Design Phase – the timeline through selection of flight experiments—

February 28, 2024: SSEP National Announcement of Opportunity (AO) for SSEP Mission 19 to the International Space Station
Announcement across U.S. via the National Center for Earth and Space Science Education (NCESSE): opportunity open to School Districts (pre-college grades 5-12); 2-Year Community Colleges; 4-Year Colleges and Universities with emphasis on Minority Serving Institutions (MSIs); and informal education and out-of-school organizations. Announcement to Canada, Japan, and member states of the European Union (EU) and the European Space Agency (ESA) via NCESSE’s international arm, the Arthur C. Clarke Institute for Space Education.

February 28 – August 22, 2024 (25 weeks): Communities Come Aboard
Education stakeholders at the community level assess the opportunity, and if interested, rapidly assess funding prospects with local foundations, businesses, and philanthropic organizations, and secure pledges of funding (Letters of Commitment of Funding).

WE CAN HELP IDENTIFY FUNDING: Regarding identifying and securing funding, NCESSE can assist if staff time is available. NCESSE found full or partial funding for 233 of the 404 SSEP community programs associated with the twenty flight opportunities to date—SSEP on the final two Space Shuttle flights, and SSEP Missions 1 through 18 to ISS. We are committed to doing the same for SSEP Mission 19 to ISS.

August 22, 2024: Final Date for Receipt of Formal Letters of Commitment of Funding
Deadline for your community to submit to NCESSE via email a formal Letter of Commitment of Funding (on letterhead of the funding organization), which states that funding is available and will be allocated to SSEP. If NCESSE is leading the fundraising, we will secure these letters.

August 22, 2024: Final Date for Go-No-Go Decision
Based on the received Letters of Commitment, NCESSE announces if the minimum of 10 flight slots required to fly the SSEP Mission 19 Payload to ISS has been achieved. Note that the minimum requirement will likely be met far earlier than August 22. All funded communities will be notified as soon as the minimum requirement is met so that they can gear up for program operations as early as possible in advance of program start. Note: NCESSE has never missed the minimum target for a SSEP flight opportunity.

September 3, 2024: SSEP begins in all participating communities

TO GET STARTED WITH SSEP IN YOUR COMMUNITY: read the Teacher and Student Resources page.

September 9, 2024: NCESSE ships 2 Demonstration Fluids Mixing Enclosure Mini-laboratory Kits to Each Participating Community.
These ‘Demo Mini-labs’, which are labeled as such, are not to be used to conduct actual experiments. They are to be used solely to demonstrate to teachers and students the design, assembly, and operation of a Mini-lab. Five additional ‘Experiment-grade Mini-labs’ will be shipped to each participating community once the flight experiment is formally selected. The Experiment-grade Mini-labs will be used by the flight team for experiment optimization, and as the actual flight and ground control mini-labs used to formally conduct the flight experiment.

October 4, 2024: Deadline for Community’s One- or Two- Mission Patch Plan to be Received by NCESSE via Email, by 5:00 PM Eastern Time (USA), (see Mission Patch page).

CRITICAL NOTES:  A plan submitted after this deadline will not be accepted, and the community will forfeit their opportunity to fly a Mission Patch(es). The plan must be emailed to John Hamel, NCESSE’s Flight Operations Manager for SSEP, at: Once received, John will determine if each Plan includes all needed information, and is consistent with all requirements necessary for a community to fly a Mission Patch(es). If a Plan is not approvable, the submitting community will be notified as soon as possible, and have until 5:00 PM ET on October 11 to submit an approvable Plan.

October 11, 2024: Deadline for Community’s One- or Two- Mission Patch Plan to be Approved by NCESSE, by 5:00 PM Eastern Time (USA), (see Mission Patch page)

CRITICAL NOTE: Plans that are deemed still incomplete by this deadline will be rejected, and the community will forfeit their opportunity to fly a Mission Patch(es).

October 16, 2024: Deadline for Signed Contract and First of Two Installments  
Final date for a signed contract between your community and SSEP to be in place; by this date SSEP must have received the signed contract and a check to Tides Center (NCESSE’s parent non-profit) for 50% of the total cost.

September 3, 2024 – November 5, 2024: 9 weeks of Experiment Design and Proposal Writing in Participating Communities
Microgravity curriculum delivered by local team of teachers; student teams design experiments, write 5-page proposals, and submit to your community’s lead organization on SSEP.

CRITICAL NOTE: All proposing teams should be required to send a Notice of Intent to propose (NoI) statement, a very short letter or email, to your community’s lead organization on SSEP by October 1, 2024, so you know how many proposals are expected from across your community, and the size of your Step 1 Review Board can be determined and assembled in advance. See the Guidance for Setting Up a Step 1 Review Board page.

November 5, 2024: Deadline for Student Team Proposals to be Submitted to Your Community’s Lead Organization for Step 1 Review

November 5-7, 2024: Proposals are processed by Your Community’s Lead Organization on SSEP and Distributed to Your Step 1 Review Board.

November 7-13, 2024: Step 1 Review Board Reviews Proposals and Selects 3 Finalist Proposals for Each Flight Slot You Have Reserved.
The selected finalist proposals are forwarded to NCESSE for SSEP Step 2 Review.

CRITICAL NOTES: Your community must only forward proposals that meet proposal requirements, as per the Proposal Requirements Checklist (found in the Flight Experiment Proposal Guide which is downloadable from the Document Library.) If the proposals are written in a language other than English, the finalist proposals must be translated into English before they are sent to SSEP for Step 2 Review.

November 14, 2024: Deadline for Finalist Proposals to be Received by NCESSE Via Email by 10:00 PM Eastern Time (USA)

CRITICAL NOTES: Proposals submitted after this deadline will be rejected and will not move on to Step 2 Review. Proposals must be emailed to Stacy Hamel, NCESSE’s Senior Flight Operations Manager for SSEP at: Once received, a cursory review will be conducted to determine if the proposals are complete. As a benchmark, 85% of all finalist proposals submitted by communities to date have been identified as incomplete during cursory review. If a proposal is incomplete, the submitting community will be notified as soon as possible, and have until 10:00 PM ET on November 20, 2024 to rectify the situation.

November 20, 2024: Deadline for Finalist Proposals to be Accepted by NCESSE, by 10:00 PM Eastern Time (USA), for Step 2 Review

CRITICAL NOTE: Proposals that are deemed still incomplete at this deadline will be rejected and will not move on to Step 2 Review.

November 21-25, 2024: Finalist Proposals are Processed by SSEP and Distributed to Step 2 Review Board.

December 3-4, 2024: Step 2 Review Board Meets and Tentatively Selects the M19 Flight Experiments

December 5-12, 2024: NCESSE Processes Step 2 Review Board Comments 
NCESSE assesses Review Board comments for each tentatively selected flight experiment. The Board’s comments may include a list of critical issues that need to be addressed by the student team before the experiment can be declared the formally selected flight experiment.

December 12, 2024: Communities Informed of Tentatively Selected Flight Experiments
NCESSE informs the Community Program Director(s) in each community which finalist proposal was tentatively selected as the flight experiment. This milestone is not associated with a public announcement.

December 12-19, 2024: Student Teams Address Any Critical Issues Identified by the Step 2 Review Board
NCESSE informs each student team what issues must be addressed before their experiment can be formally selected as the flight experiment. Student teams need to be prepared to rapidly address issues across a broad range of topics, including: experiment design, choice of fluids/solids to be flown, requested special handling during transport of the experiment, requested Crew Interaction Days, requested crew interactions aboard ISS, and experimental analysis protocols. NCESSE will work closely with each team to address any issues, and using a document called the Preliminary Flight Safety Review Form, lock down all the experiment details needed for Nanoracks to review and approve the experiment as the formally selected flight experiment.

December 20, 2024: Flight Experiments Formally Selected (note – this is a target date)
NCESSE informs a community of their formally selected flight experiment. The community is now free to make a public announcement.

CRITICAL NOTES: This date is dependent on Nanoracks review and approval of each Preliminary Flight Safety Review
Form. While this is a target date, it can, and has slipped on prior missions. The community is not free to make public
announcements until NCESSE informs the community that the tentatively selected flight experiment has been formally selected through Nanoracks review and approval.

December 20, 2024: Deadline for Second and Final Installment
Deadline for NCESSE to receive second and final installment from your community, with a check to Tides Center (NCESSE’s parent non-profit) for 50% of total cost, allowing program to proceed to the Flight Operations Phase.

December 20, 2024: NCESSE Ships 5 Experiment-Grade Fluids Mixing Enclosure Kits to Each Participating Community
These ‘Experiment-grade Mini-labs’ will be used by the flight team for: i) experiment optimization, and ii) as the actual flight and ground control mini-labs in which the experiment will be conducted on ISS and on the ground. No more than 2 Experiment-grade Mini-labs should be used for optimization; 1 Mini-lab should be carefully set aside for use as the flight experiment to be shipped to Nanoracks in Houston for payload integration; and 2 Mini-labs should be carefully set aside for use as the ground control experiments.

Phase 2: Flight Operations Phase – the timeline through Return to Earth of flight experiments—

December 20, 2024 – February 5, 2025: 7 weeks of Experiment Testing, Refinement, and Optimization Using the FME Mini-lab 
Over this 7-week period the student team is directed to carry out refinement and optimization of their experiment in the FME mini-lab.

CRITICAL NOTES: By the end of this period the student team must fully determine the Experiment Samples (fluids and solids) to be used, and the maximum volumes and concentrations of these samples. After this deadline, there will be NO ability to: i) add new fluids and solids, or ii) increase volumes and/or concentrations of those fluids and solids.  By this deadline, student researchers must also have a good understanding of: i) any Special Handling Requirements during transport to and from ISS, and ii) the baseline Timeline of Crew Interactions, which includes both the proposed Crew Interaction Days and proposed Crew Interactions aboard ISS. NCESSE will work closely with each team to capture these experiment details, which are critical for Flight Safety Review by NASA Toxicology, using a document called the Final Flight Safety Review Form.

February 5, 2025: Deadline for NCESSE to Receive the Final Flight Safety Review Form from Student Teams by 5:00 PM ET
NCESSE will email this Final Flight Safety Review Form to Teacher Facilitators by January 13, 2025.

February 5-11, 2025: NCESSE Works with Student Teams to Lock Down Experiment Details for NASA Flight Safety Review
NCESSE will work with each student team to correct and finalize the Final Flight Safety Review Form (as needed). Once complete, the Form will be forwarded to Nanoracks for review and approval. Once approved, Nanoracks will create and submit a Master List of Experiment Samples reflecting all Mission 19 flight experiments, including maximum volumes and concentrations for all samples, and forward to NASA Toxicology at Johnson Space Center for Flight Safety Review.

February 12, 2025: NASA Toxicology Receives Master List of Experiment Samples for Flight Safety Review
NASA Toxicology requires receipt of the Master List 120 days in advance of launch to carry out the Flight Safety Review.

CRITICAL NOTE: Launch must therefore take place no earlier than June 11, 2025(note this date puts a constraint on ferry vehicles available for experiment transport to ISS).

February 12, 2025 through Approximately 2 Months Before Launch: Student Teams Can Continue to Refine and Optimize Their Experiment
Once the Master List of Experiment Samples is provided to NASA Toxicology, student flight teams can continue to refine and optimize their experiments up through approximately 2 months before launch. However, given Flight Safety Review is now underway, student teams need to be aware of the following limitations on experiment refinement during this period –

CRITICAL CONSTRAINTS: Any modification to the approved list of experiment samples (fluids and solids) for an experiment is now limited to REDUCING concentrations and volumes. The addition of new samples is NOT allowed. A sample can be removed entirely from the experiment’s list of samples, which corresponds to reducing the volume to 0. Critical modifications to Special Handling Requirements during transport to and from ISS, Crew Interaction Days, and Crew Interactions with the experiment aboard ISS are still possible in consultation with NCESSE and Nanoracks.

Approximately 2 Months Before Launch: Student Teams Lock Down the Final Flight Experiment Configuration
NCESSE will work with each student flight team to fully define the final flight experiment configuration, including all information listed in the Critical Constraints above. This will be accomplished using the Flight Configuration Agreement, which will be signed by the Teacher Facilitator, Nanoracks and NCESSE confirming all details are accurate and final.

March 4, 2025: Deadline for NCESSE to Receive Mission Patch(es) to Fly to ISS, by 5:00 pm ET (USA), (see Mission Patch page)


Flight Operations Milestones Associated with Launch and Return to Earth:
The following milestones are provided relative to the time of handover of the flight experiment mini-lab to Nanoracks in Houston. These milestones are subject to the very fluid nature of launch operations, and should be viewed as a nominal operations profile that is subject to significant change.

CRITICAL NOTE: the most current public information NCESSE has regarding the launch date for Mission 19 to ISS is found on the Mission 19 to ISS main page.

T=0, Handover: Deadline for Nanoracks to Receive All Mini-labs from Flight Experiment Teams
Communities will ship the flight mini-lab to Nanoracks in Houston for delivery approximately 18 days before launch. Once received, Nanoracks will log receipt of shipment, apply a second set of zip ties and a sealant to each of the end caps, heat seal level 2 and 3 containment bags around each mini-lab, and load the mini-lab into the SSEP Mission 19 Payload Boxes.
Current Target: Late Spring/Summer 2025 (Launch Minus 18 Days)

T + 12 Days: SSEP Mission 19 Payload Turned Over by Nanoracks to NASA for Vehicle Integration
Current Target: Late Spring/Summer 2025 (Launch Minus 6 Days)

T + 16 Days: SSEP Mission 19 Payload is Loaded into Ferry Vehicle
Current Target: Late Spring/Summer 2025 (Launch Minus 2 Days)

T + 18 Days: Launch of SSEP Mission 19 Payload to ISS
Current Target: Late Spring/Summer 2025

T + 3 Weeks: Payload Transferred from Ferry Vehicle to ISS
Current Target: Late Spring/Summer 2025 (Launch Plus 2-3 Days)

T + 7-9 Weeks: SSEP Mission 19 Payload Returns to Earth
Current Target: Summer 2025 (Launch Plus Approximately 4-6 Weeks)

Return to Earth + 24-72 Hours: SSEP Mission 19 Payload Received by Nanoracks in Houston and Flight Mini-labs Shipped Directly To Experiment Teams
Current Target:
Summer 2025
Upon receipt, Nanoracks will process the mini-labs, including logging receipt and checking for obvious signs of any anomalies. Upon completion of processing, the mini-labs are shipped to communities via FedEx. Mini-labs are shipped using the speed and Special Handling Requirements defined in advance by the community. International communities will need to have their mini-lab shipped to a U.S. address such as an embassy or a consulate, have a representative pick up their mini-lab in Houston, or make other international transport arrangements that take into account all customs requirements.

Receipt of Flight Mini-lab by Student Team + 1-10 days: Submission of the Mini-laboratory Inspection in Advance of Harvesting Report
Current Target: Summer 2025

The Mini-laboratory Inspection in Advance of Harvesting Report must be completed and submitted to NCESSE within 10 days of your student team’s receipt of the flight mini-laboratory, and preferably much sooner. This report allows the student team to formally provide details of their visual inspection of both the flight and ground control mini-labs and assess if any operational anomalies are observed. This report must be submitted within 10 days of receipt of your flight experiment if we are to report any anomalies to the launch services provider.

The Student Spaceflight Experiments Program (SSEP) is a program of the National Center for Earth and Space Science Education (NCESSE) in the U.S., and the Arthur C. Clarke Institute for Space Education internationally. It is enabled through a strategic partnership with DreamUp PBC and NanoRacks LLC, which are working with NASA under a Space Act Agreement as part of the utilization of the International Space Station as a National Laboratory. SSEP is the first pre-college STEM education program that is both a U.S. national initiative and implemented as an on-orbit commercial space venture.