Lunar Space Environment Monitor (LUSEM), KASI¶
IM-3 · manifested · partner payload
A Korean energetic-particle detector: two pairs of solid-state telescopes, one looking up and one down in each pair, that count electrons and ions above 50 keV arriving from space and reflected from the surface. It tracks how the near-surface particle environment changes as the Moon passes in and out of Earth's magnetotail.
PI: Young-Jun Choi (KASI)
Built by: Korea Astronomy and Space Science Institute (KASI), with Kyung Hee University (Jongho Seon's team); manufactured by Satrec Initiative (partner agency)
| Technology | science instrument (energetic particles, space weather) |
| Moon Base need | DN-012 L (The study's reading. LUSEM measures charged particles at the surface, which is part of DN-012 L (surface radiation and space weather). The fit is partial: DN-012 L asks for long-term South Pole data, including neutrons up to at least 100 MeV; LUSEM measures electrons and ions only, for one lunar day at Reiner Gamma. KASI's partner says the particles matter for astronaut health and spacecraft electronics. NASA's Moon Base page puts IM-3 in Phase One.) |
| Route onto CLPS | partner; No NASA call. KASI proposes payloads for CLPS landers through the KASI-NASA Exploration Working Group, and Korea's science ministry funds those it selects on scientific merit and technical readiness. NASA named LUSEM for the IM-3 lander in November 2021. Korea's ministry calls it the first joint project after Korea signed the Artemis Accords.; 2021-11-17 |
| Timeline | first funding 2020 (NRF grant number 2020M1A3B7040417); earlier KASI funding not in public sources; first flight test 2018 (KSEM predecessor on GK2A); selected 2021-11-17 (NASA's CP-11 award naming LUSEM); launch no earlier than the first part of 2027 (NASA, September 2026, per Wikipedia). LUSEM was completed in 2023 and shipped to Intuitive Machines in September 2023.; landing not in public sources |
| On the Moon | not yet flown |
| FO | none |
Flights before the Moon¶
- Earth orbit or deep space: Korea's geostationary weather satellite GEO-KOMPSAT-2A (Chollian-2A), carrying KSEM, Kyung Hee University's space weather particle instrument, 2018. KASI says LUSEM draws on the heritage of KSEM, the Korea Space Environment Monitor, a space weather instrument that Kyung Hee University built for Chollian-2A, launched in 2018. Same university team; a predecessor in geostationary orbit, not the lunar instrument. Which KSEM parts carried over is not stated.
"Attributed to the heritages"
— DALO-Discovery Across Lunar Observations"of KSEM (Korea Space Environment Monitor) aboard the Korean"
— DALO-Discovery Across Lunar Observations, (continues: geostationary meteorological satellite (Geo-KOMSAT-2A, GK2A))"the development of a space weather observation instrument for the Chollian-2A satellite in 2018"
— Kyung Hee University Develops South Korea's First Lunar Lander Science Instrument, Kyung Hee University
Heritage hardware¶
- design heritage (same team): LUSEM's sensor head, two solid-state telescopes per pair (one for electrons, one for ions, facing up and down), follows the team's KSEM work. Its ranges are 50 keV to 3.8 MeV for electrons and 50 keV to 22.5 MeV for protons.
"Its detection range—50 keV to 3.8 MeV for electrons and 50 keV to 22.5 MeV for protons"
— Kyung Hee University Develops South Korea's First Lunar Lander Science Instrument"composed of two solid-state telescopes (SST) that enable bidirectional observations"
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…
Funding before the lunar flight¶
- Korea's Ministry of Science and ICT, through the National Research Foundation of Korea (grant 2020M1A3B7040417, KASI's DALO lunar payload projects). Amount not public. Foreign funding: no SBIR or USAspending record applies. NASA pays only the delivery, inside the CP-11 task order. (MSIT / National Research Foundation of Korea; 2020 on): amount not in public sources
"National Research Foundation of Korea (NRF) under"
— hou.usra.edu: 1494.pdf"grant No. 2020M1A3B7040417, which is funded by"
— hou.usra.edu: 1494.pdf"funded by the Ministry of Science and ICT of Korea (MSIT)"
— ntrs.nasa.gov: CLPS2025LPSCv1.pdf
How it got onto CLPS¶
"KASI-NASA Exploration Working Group."
— hou.usra.edu: 1494.pdf"selected based on their scientific merit and expected"
— hou.usra.edu: 1494.pdf"NASA announced in November 2021 that LUSEM of Korea will be aboard the Intuitive Machines’ unmanned lunar lander, Nova-C"
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…"LUSEM is managed by the Korea Astronomy and Space Science Institute (KASI) in South Korea."
— NASA Selects Intuitive Machines for New Lunar Science Delivery - NASA"As the first collaborative project launched after signing the Artemis Agreement"
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…
On the Moon¶
Waiting for IM-3 since its delivery in 2023.
"LUSEM was similarly qualified and delivered in 2023."
— Wikipedia article "IM-3", revision 1376815437 of 2026-09-26T11:03:10Z, revision 1376815437
FO's role¶
Grade: none. No FO project, flight or report names LUSEM, KASI, Kyung Hee University or Satrec Initiative. It is a Korean partner payload; FO's calls are for US entities, so none was expected. Its flight lineage is a Korean satellite instrument (KSEM, 2018). The study's earlier traceback grade (none found) stands.
"International partner payload delivered under NASA's CLPS order. Nothing in the FO sources."
— earlier finding of this study (not a public source)
Who built it¶
"Lead Development Organization: Korea Astronomy and Space Science Institute (KASI)"
— CP-11 Science Payloads - NASA Science"Payload PI: Young-Jun Choi"
— CP-11 Science Payloads - NASA Science"LUSEM is a scientific payload developed by KASI in collaboration with Professor Jongho Seon’s research team"
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…"The development was undertaken in partnership with the domestic company Satrec Initiative, which was responsible for manufacturing."
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…
Moon Base need¶
"Measure the radiation environment on the lunar surface at the south pole."
— Moon to Mars knowledge base: DN-012 L: In situ lunar surface radiation environment measurements and space weather monitoring, description"Key Measurement: Charged particles of ≥ 50 keV, separating ions and electrons"
— CP-11 Science Payloads - NASA Science"These high-energy particles can have implications for the health of astronauts, the functionality of spacecraft electronics"
— Korean Scientific Payload For Observing Lunar Space Environment Begins Transfer To US For Schedul…"planned for Phase One of Moon Base development"
— Moon Base Phases - NASA, IM-3 listed below
Open questions¶
- Korea's spending on LUSEM: not in public sources.
- Which parts of KSEM (GK2A, 2018) LUSEM reuses: the sources say only that it draws on KSEM's heritage.
- How long the stored instrument (delivered 2023) can wait before retest: not in public sources.