Planetary Simulant Database: MPACS Mechanical Porous Ambient Comet Simulant

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Mineral Abundance
Portland cement (binder) variable
Pumicite grains (aggregate) variable

Bulk Chemistry

No data available

Physical Properties

Property Value
Density 0.15-0.67 g/cm3
Porosity 75.5-94%
Cone penetration resistance 0.55-7.3 MPa
Unconfined compressive strength 45 kPa-1.0 MPa
Simulant Name: MPACS Mechanical Porous Ambient Comet Simulant
Current Status: Created for internal use
Developed By: Jet Propulsion Laboratory
Available From: N/A
Publications: Carey, E. M. et al. (2017), Development and characteristics of Mechanical Porous Ambient Comet Simulants as comet surface analogs. Planetary and Space Science, 147, 6-13.

MPACS is a geotechnical simulant designed to replicate the mechanical properties of cometary nuclei surfaces. It was developed by JPL to have extremely low density, high porosity, and strength profiles within a desired range. The simulant is produced by mixing a commercial quick setting cement with finely ground pumice in water, then casting in a mold and curing for >21 days.

The recipe and procedure are available, and it isn’t clear whether there is any plans to mass produce or distribute the simulant to the community.


Photograph of the MPACS simulant from Carey et al. 2017: