Overview
Overview
The NU-LHT series was designed by the USGS in the late 2000s as general use lunar highlands simulants. They are based on the average chemical composition of Apollo 16 regolith samples. NU-LHT was made from a combination of Stillwater Norite, Anorthosite, and Hartzburgite, and Twin Sisters Dunite; partially and fully melted Stillwater mill waste was added as "pseudo-agglutinates" and "good glass", respectively. The -2M version also included natural ilmenite, synthetic whitlockite, natural fluor-apatite, and natural pyrite.
The -1M version is composed of 80% crystalline material, 16% pseudo-agglutinate, and 4% good glass, while the -2M version is 65% crystalline material, 30% pseudo-agglutinate, and 5% good glass.
The -1D version is a finely-ground dust simulant, and -2C is a synthetic breccia. The -3M version removed the pseudo-agglutinates from NU-LHT-2M because it was designed for extensive mechanical testing under which the pseudo-agglutinates would likely break down.
The USGS is currently looking into re-starting its simulant efforts.[1]
Pros and Cons
Pros and Cons
Pros
Pros
- Similar particle size distribution to lunar highlands regolith
- Similar composition to lunar highlands
- Similar particle shape/abrasive properties to lunar highlands regolith
General Properties
General Properties
Particle size distribution of NU-LHT-2M[2]
General Properties
General Properties
| Particle Shape Range | Particle Size Range (μm) | Mean Particle Size (μm) |
|---|---|---|
| - | - | - |
| Particle Size Distribution (by site/sample) | Chemical Composition (by sample/site) | Mineralogical Composition |
|---|---|---|
| - | - | - |
| Texture |
|---|
| - |
Modal Mineralogy[3]
Modal Mineralogy[3]
| Mineral | Apollo 16 64001/64002 (%) |
NU-LHT-1M Abundance (%) |
NU-LHT-1M Prototype (%) |
NU-LHT-2M Abundance (%) |
|---|---|---|---|---|
| Lithic fragments | 31.1 | - | - | - |
| Glass | 8.9 | 22.4 | 19.7 | 7.2 |
| Agglutinates | 32.5 | 29.0 | - | 23.5 |
| Plagioclase | 23.3 | 38.8 | 43.4 | 54.9 |
| Olivine | - | 2.9 | - | 9.5 |
| Norite | - | - | 30.0 | - |
| Harzburgite | - | - | 6.1 | - |
| Clinopyroxene | 0.6 | 2.0 | - | 4.0 |
| Orthopyroxene | 3.2 | 4.4 | - | 0.2 |
| Spinel minerals | 0.03 | 0.05 | - | 0.01 |
| Fe-sulfide | 0.01 | 0.00 | - | 0.04 |
| Ca-phosphates | 0.12 | - | - | 0.43 |
| Ilmenite | 0.1 | 0.3 | 0.73 | 0.2 |
| Native iron | 0.01 | - | - | - |
| Other (sim. only) | - | 0.02 | - | 0.01 |
| Total | 100 | 100 | - | 100 |
Major Element Chemistry
Major Element Chemistry
| Oxide | Apollo 16 Avg. Soil wt. %[4] |
NU-LHT-1M[1] | NU-LHT[5] |
|---|---|---|---|
| SiO2 | 45 | 47.6 | 46.6 |
| Al2O3 | 26.7 | 24.4 | 21.55 |
| FeO | - | 4.3 | 5.08 |
| Fe2O3 | - | - | - |
| MgO | 6.14 | 8.5 | 9.5 |
| CaO | 15.3 | 13.1 | 12.6 |
| Na2O | 0.457 | 1.4 | 0.965 |
| K2O | 0.12 | - | 0.12 |
| TiO2 | 0.595 | - | 0.115 |
| P2O5 | - | - | 0.07 |
| MnO | - | - | 0.09 |
| Cr2O3 | - | - | 0.12 |
| V2O5 | - | - | - |
| LOI + H2O | - | - | 2.74 |
Geomechanical and Physical Properties
Geomechanical and Physical Properties
Geomechanical Properties for NU-LHT-2M
Geomechanical Properties for NU-LHT-2M
| Hardness (Mohs scale) | Specific Gravity (g/cm3) | Angle of Repose (°) | Void Ratio |
|---|---|---|---|
| - | 2.749[2] | - | 0.332 - 1.004[2] |
| Density (g/cm3) | |||
|---|---|---|---|
| Bulk | Relative Max | Relative Min | |
| 1.648 - 1.869[2] | 2.057[2] | 1.367[2] | |
| Triaxial: Shear Strength | Uniaxial | ||
|---|---|---|---|
| Cohesion (kPa) | Friction Angle (°) | Young's Modulus (MPa) | Tensile Strength (kPa) |
| - | 36-40.7[2] | - | - |
Simulant Development
Lab Analytical Results
Simulant Development
Lab Analytical Results
Pending analyses.
Safety
Safety
Please view the NU-LHT-2M Safety Data Sheet (SDS) for specifications, PPE requirements, and hazards.
NU-LHT is recommended for geotechnical testing that involves loose or compacted simulant. NU-LHT is also recommended for abrasion testing and ISRU testing. View the Simulant Testing Matrix and/or contact the JSC Simulant Development Laboratory for information concerning simulant recommendations.
Excavation / Flow
Excavation / Flow
NU-LHT-1M | Recommended
It has been demonstrated that pseudo-agglutinates affect geomechanical behavior that may be important to excavation.
It has been demonstrated that pseudo-agglutinates affect geomechanical behavior that may be important to excavation.
NU-LHT-2M | Recommended
It has been demonstrated that pseudo-agglutinates affect geomechanical behavior that may be important to excavation.
It has been demonstrated that pseudo-agglutinates affect geomechanical behavior that may be important to excavation.
NU-LHT-1D | Not Recommended
Unrealistically fine PSD.
Unrealistically fine PSD.
NU-LHT-2C | Most Recommended
It has been demonstrated that pseudo agglutinates affect geomechanical behavior that may be important to excavation.
It has been demonstrated that pseudo agglutinates affect geomechanical behavior that may be important to excavation.
Drilling
Drilling
NU-LHT-1M | Recommended
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
NU-LHT-2M | Recommended
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
NU-LHT-1D | Not Recommended
Unrealistically fine PSD.
Unrealistically fine PSD.
NU-LHT-2C | Most Recommended
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith, good PSD.
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith, good PSD.
Abrasion / Wear
Abrasion / Wear
NU-LHT-1M | Recommended
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
NU-LHT-2M | Recommended
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Fidelity to mineral and glass % should yield appropriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
NU-LHT-1D | Not Recommended
Unrealistically fine PSD for many uses.
Unrealistically fine PSD for many uses.
NU-LHT-2C | Most Recommended
Fidelity to mineral and glass % should yield approriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Fidelity to mineral and glass % should yield approriate abrasiveness. Presence of pseudo-agglutinates may aid fidelity to regolith.
Oxygen Production
Oxygen Production
NU-LHT-1M | Recommended
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite. High Fe in silicates relative to reference, which will slow reduction.
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite. High Fe in silicates relative to reference, which will slow reduction.
NU-LHT-2M | Recommended
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite, phosphates, and sulfides; the presence of which is realistic but possibly hazardous to ISRU processes. High Fe in silicates relative to reference, which will slow reduction.
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite, phosphates, and sulfides; the presence of which is realistic but possibly hazardous to ISRU processes. High Fe in silicates relative to reference, which will slow reduction.
NU-LHT-1D | Not Recommended
Should be similar to NU-LHT-1M but possibly with lower FeO.
Should be similar to NU-LHT-1M but possibly with lower FeO.
NU-LHT-2C | Most Recommended
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite, phosphates, and sulfides; the presence of which is realistic but possibly hazardous to ISRU processes. High Fe in silicates relative to reference, which will slow reduction.
Chemistry: Slightly low FeO relative to lunar reference (~4 vs. 5 wt.%) but significantly closer than other simulants. Mineralogy: Contains ilmenite, phosphates, and sulfides; the presence of which is realistic but possibly hazardous to ISRU processes. High Fe in silicates relative to reference, which will slow reduction.
Human Health Studies
Human Health Studies
NU-LHT-1M | Recommended
It lacks the added phosphates and sulfides of NU-LHT-2M; reasonable PSD but too coarse in fine fraction.
It lacks the added phosphates and sulfides of NU-LHT-2M; reasonable PSD but too coarse in fine fraction.
NU-LHT-2M | Recommended
Reasonable PSD but too coarse in fine fraction.
Reasonable PSD but too coarse in fine fraction.
NU-LHT-1D | Not Recommended
It lacks the added phosphates and sulfides of NU-LHT-2M; good PSD in fine fraction.
It lacks the added phosphates and sulfides of NU-LHT-2M; good PSD in fine fraction.
NU-LHT-2C | Most Recommended
Good PSD.
Good PSD.
- ↑ Jump up to: 1.0 1.1 Referenced from the Colorado Schools of Mines’ Planetary Simulant Database, which has been taken offline. A new NASA simulant database is in development.
- ↑ Jump up to: 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Zeng et al. (2010). Geotechnical Properties of NU-LHT-2M Lunar Highland Simulant. Journal of Aerospace Engineering, 23(4): 213-218.
- ↑ Jump up to: 3.0 3.1 Schrader, C. M., Rickman, D. L., McLemore, C. A., and Fikes, J. C. (2010). Lunar Regolith Simulant User's Guide. NASA/TM-2010-216446
- Jump up ↑ Korotev, R. L., (1997). Some things we can infer about the Moon from the composition of the Apollo 16 regolith. Meteoritic & Planetary Science, 32, 447-478.
- Jump up ↑ https://www.nasa.gov/sites/default/files/atoms/files/conf_pres_ptmss2008_schrader.pdf