LASSO — DARPA Lunar Partnership¶
The Lunar Assay via Small Satellite Orbiter (LASSO) is a DARPA-led, NASA STMD-partnered mission to map lunar water ice from very low lunar orbit (~10 km altitude). It represents the first DARPA partnership in the SST/SSDS portfolio, and the program's first deep-space operational mission beyond LEO CubeSat demos.
Last updated: 2026-04-14 (session 26)
Mission Overview¶
| Field | Detail |
|---|---|
| Lead agency | DARPA Strategic Technology Office (STO) |
| NASA partner | Space Technology Mission Directorate (STMD) |
| Program manager | Steven Chambers (DARPA) |
| IAA signed | September 23, 2025 (NASA IAA) |
| Solicitation | DARPA-PS-25-07, released April 14, 2025 |
| Abstracts due | May 27, 2025 (oral presentations followed) |
| TechPort entry | None as of April 2026 |
| Award type | Other Transaction (OT) |
Objectives¶
Dual-purpose mission:
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Water ice prospecting: Map the entire lunar surface within 4 years of lunar orbit arrival. Identify all regions with ≥5% water concentration at ≤4 km² resolution, with ≥90% confidence. Must produce a "proven reserve model" for ISRU.
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Autonomous low-lunar-orbit operations: Stress-test propulsion and GN&C in very low lunar orbits (~10 km altitude) where mascons (mass concentrations from ancient asteroid bombardment) create severe gravitational perturbations. Demonstrate continuous dynamic repositioning without continuous ground contact.
Program Phases¶
| Phase | Duration | Scope | Selection |
|---|---|---|---|
| 1A | 6 months | Conceptual design study | Multiple performers |
| 1B | 18 months | Detailed subsystem/satellite design through CDR | Downselect |
| 2 | 12 months | Build spacecraft | Single performer (possibly 2) |
| Launch | TBD | NASA arranges launch; DARPA's involvement ends with completed spacecraft | — |
Status (April 2026): Solicitation closed June 3, 2025. Phase 1A awards not yet publicly announced.
SST/SSDS Heritage Connections¶
Expectation: LASSO's dual requirements (cislunar autonomous nav + low-orbit station-keeping propulsion) align precisely with SST's deepest technology threads. Multiple SST alumni companies and technologies are plausible candidates.
Cislunar navigation (directly relevant)¶
| SST Project | Technology | LASSO Relevance |
|---|---|---|
| 106820 CAPS/CAPSTONE (Advanced Space) | Peer-to-peer cislunar nav, NRHO demonstration | LASSO needs autonomous nav beyond Earth-based tracking. CAPS proved it works. |
| 155359 Autonomous Optical Nav (GA Tech, Christian) | Crater-based, star-based optical nav | LASSO explicitly needs alternative nav methods to Deep Space Network. |
| 106826 Surface Feature Nav (UT Austin, Jones) | Crater-based lunar positioning | Direct overlap: lunar surface feature recognition for positioning. |
| 106828 Optomechanical Accelerometer (UCLA, Wong) | High-sensitivity accelerometry | Mascon gravity mapping requires precise inertial sensing. |
| 155361 Microphotonic Clocks (Caltech, Vahala) | Ultra-stable timing | Autonomous nav requires onboard timing reference. |
The LunaNet PNT stack (2020 SST cycle) maps almost perfectly onto LASSO's requirements. Four independent SST projects built complementary layers of cislunar infrastructure. LASSO is the first mission concept that would need all four simultaneously. See Emergent Architecture Stack archetype.
Propulsion for low-lunar-orbit station-keeping¶
| SST Project | Technology | LASSO Relevance |
|---|---|---|
| 116400 SSEP/NGHT-1X (Northrop Grumman, GRC) | Sub-kW Hall thruster | Long-duration station-keeping in perturbed orbit. |
| 106825 Courier SEP Module (ExoTerra/Voyager) | Halo thruster + solar arrays | Compact EP module for sustained maneuvering. |
| 155369 GPDM (MSFC) | ASCENT dual-mode (chemical + electric) | Chemical for emergency burns, electric for sustained orbit maintenance. |
| 106834 3D Hybrid Propulsion (USU, Whitmore) | Hybrid for lunar landing/sample return | Developed explicitly for lunar mission profiles. |
LASSO's 10 km orbit requires frequent, responsive maneuvering — a dual-mode system (electric for routine station-keeping, chemical for emergency collision avoidance with terrain) seems architecturally ideal.
Communications¶
| SST Project | Technology | LASSO Relevance |
|---|---|---|
| 106823 5G Ka-band Phased Array (SDSU, Sharma) | Dual-beam Ka-band comms | Earth-to-lunar comms without DSN dependency. |
| 94065 CLICK laser crosslinks (MIT, Cahoy) | Optical inter-satellite links | If LASSO uses relay architecture. |
Potential SST alumni bidders¶
Companies with both SST heritage and cislunar/DoD positioning that could plausibly bid on LASSO:
| Company | SST Heritage | LASSO-Relevant Capability | Likelihood |
|---|---|---|---|
| Advanced Space | CAPSTONE cislunar nav | Autonomous cislunar positioning, AFRL Oracle | High — closest capability match |
| Tyvak/Terran Orbital (Lockheed Martin) | PTD bus provider | Smallsat bus with deep-space heritage | Medium — now defense prime subsidiary |
| ExoTerra/Voyager | Courier SEP module | EP for sustained maneuvering | Medium — SDA production experience |
| Blue Canyon Technologies (Raytheon) | Starling swarm bus | Smallsat bus + ADCS | Medium — less cislunar experience |
| Starfish Space | SSPICY RPO | Autonomous proximity ops | Low — LEO focus |
Confidence: speculative. No Phase 1A awards announced. These are informed guesses based on SST portfolio analysis.
Significance for SST/SSDS¶
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Program evolution: LASSO is the clearest signal that SST's portfolio has matured from LEO CubeSat demos to cislunar operational missions. The SST→SSDS rename (2025) and LASSO partnership are temporally correlated.
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DARPA partnership is new: SST/SSDS has partnered with DoD through SDA production contracts (Tyvak, ExoTerra) and AFRL awards (Advanced Space), but never through a formal interagency agreement with DARPA. LASSO makes the civil-defense nexus explicit.
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Heritage convergence: If an SST alumni company wins LASSO, the infusion story is complete: SST funded the components → SST flew them individually → DARPA integrates them for an operational deep-space mission. This would be the longest and most ambitious SST maturation arc yet.
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Contrast with Lunar Flashlight: Both target lunar ice. Lunar Flashlight was a 6U CubeSat with a $20M budget that failed due to propulsion. LASSO is a DARPA-scale mission with higher risk tolerance and more resources. If LASSO succeeds, it validates the "try cheap, learn, then do it right" philosophy.
Open Questions¶
- Which companies were selected for Phase 1A? (Not yet public as of April 2026)
- Does any LASSO Phase 1A team include SST alumni companies or PIs?
- Will LASSO appear as a TechPort project under SSDS, or only under DARPA?
- What is the expected launch date? (Not publicly stated)
- What instrument(s) will detect subsurface water ice? (Neutron spectrometer? Radar? NIR?)
Cross-References¶
- SST→SSDS Program Rename — program evolution context
- LunaNet PNT Stack — 4 SST projects building LASSO-relevant architecture
- Advanced Space — CAPSTONE cislunar nav heritage
- Emergent Architecture Stack archetype — LunaNet as LASSO precursor
- Lunar Flashlight — prior SST lunar ice mission (partial failure)
- Smallsat Propulsion — propulsion options for LASSO orbit maintenance
- GPDM Convergence — multi-pipeline integration pattern that LASSO might replicate
Sources: DARPA LASSO program page | NASA HESTO solicitation notice | SpaceNews coverage | NASA-DARPA IAA (PDF) | Payload Space coverage