Mars global simulant MGS-1: A Rocknest-based open standard for basaltic martian regolith simulants

May combine two claims.

Crystalline carbonates were not detected in Rocknest, but evolved gas analysis suggests that one or more carbonate-bearing phases is present.

“Crystalline carbonates were not detected in Rocknest, but evolved gas analysis suggests that one or more carbonate-bearing phases is present (Sutter et al., 2017), such that a mixture could be present, or the carbonates could be poorly crystalline.”

• cites Sutter et al., 2017 sourceSupported

May combine two claims.

The detection of evolved ClO4 in Rocknest suggests that a mixture of (per)chlorate salts is likely present, or they are present as amorphous/adsorbed species.

“This suggests that a mixture of such salts is likely present, or they are present as amorphous/adsorbed species.”

• cites Archer et al., 2014 sourcePartly supported

  Section 3.3 (page unavailable) says evolved O₂ is consistent with decomposition of an oxychlorine salt such as perchlorate; it does not report detection of evolved ClO₄. Sections 3.1 and 3.2 favor Ca-perchlorate while leaving Mg-perchlorate possible, but do not conclude that a mixture is likely or that the salts occur as amorphous or adsorbed species. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

No crystalline (per)chlorate salts were detected in Rocknest above the ~1 wt.% detection limit, but evolved ClO4 was detected.

“No crystalline (per)chlorate salts were detected in Rocknest above the ~1 wt.% detection limit, but evolved ClO4 was detected (Archer et al., 2014).”

• cites Archer et al., 2014 sourcePartly supported

  Section 3.1 (page unavailable) says CheMin did not detect a perchlorate salt in Rocknest and that estimated abundances were below its detection limits. Section 3.3 (page unavailable) reports evolved O₂ and chlorinated hydrocarbons consistent with perchlorate decomposition, not detection of evolved ClO₄. The cited passages also do not establish a ~1 wt.% detection limit for (per)chlorate salts. (LLM, conf=0.87)

  Experimental — accuracy not yet measured

May combine two claims.

The soil itself has a basaltic composition, derived from a globally basaltic crust.

“The soil itself has a basaltic composition (Yen et al., 2005; Ming and Morris, 2017), derived from a globally basaltic crust (McSween et al., 2009).”

• cites Yen et al., 2005 sourceNot checked — no full text of the source
• cites Ming and Morris, 2017Supported
• cites McSween et al., 2009 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Oxychlorine species are present in martian soil and could include (per)chlorate salts and/or peroxide species; nitrates are also present.

“Oxychlorine species are also present in martian soil and could include (per)chlorate salts (Hecht et al., 2009; Sutter et al., 2017) and/or peroxide species (Clancy et al., 2004; Crandall et al., 2017). Nitrates are also present (Stern et al., 2015).”

• cites Hecht et al., 2009 sourceNot checked — no full text of the source
• cites Sutter et al., 2017 sourceSupported
• cites Stern et al., 2015 sourceSupported

May combine two claims.

Unit cell parameters for Rocknest minerals indicate ~An57 plagioclase, a mixture of augite and pigeonite, and ~Fo40 olivine.

“Unit cell parameters for Rocknest minerals indicate ~An57 plagioclase (Bish et al., 2013), a mixture of augite and pigeonite (Bish et al., 2013), and ~Fo40 olivine (Morris et al., 2015).”

• cites Bish et al., 2013 sourceSupported
• cites Morris et al., 2015Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

The surface of Mars is covered by an unconsolidated regolith produced by the combined action of impact comminution, physical erosion by wind, water, and lava, and chemical weathering by fluids and oxidants.

“The surface of Mars is covered by an unconsolidated regolith produced by the combined action of impact comminution, physical erosion by wind, water, and lava, and chemical weathering by fluids and oxidants (mostly early in the history of Mars) (McCauley, 1973; Malin and Edgett, 2000; Golombek and Bridges, 2000; Goetz et al., 2005; Yen et al., 2005; Murchie et al., 2009).”

• cites McCauley, 1973 sourceNot checked — no full text of the source
• cites Malin and Edgett, 2000 sourceNot checked — no full text of the source
• cites Golombek and Bridges, 2000 sourcePartly supported

  The Martian Surface Layer discussion describes sand and dust on Mars and identifies impact, volcanic, and mechanical weathering as sources of sand; it also discusses wind erosion and evidence for a wetter past. It does not establish that Mars is covered by an unconsolidated regolith produced by all the listed processes, particularly erosion by lava and chemical weathering by fluids and oxidants. Page numbers are unavailable in our copy. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

May combine two claims.

Most older simulant varieties contain almost no sulfur, whereas martian regolith contains up to 6 wt.% SO3, assuming all sulfur is in the form of sulfate.

“Most of the older simulant varieties contain almost no sulfur, whereas martian regolith contains up to 6 wt.% SO3 (assuming all S is in the form of sulfate; Yen et al., 2005; Ming and Morris, 2017).”

• cites Yen et al., 2005 sourceNot checked — no full text of the source
• cites Ming and Morris, 2017Partly supported

  The Chemical Properties section (Table 1; page unavailable) reports 4.90 wt.% SO3 for average Martian soil, supporting the presence of sulfur at roughly the claimed level. But it also reports 7.42 wt.% for dust and a soil maximum of 35.06 wt.%, so 6 wt.% is not an upper limit. The cited paper does not address sulfur in older simulants or state the assumption that all sulfur is sulfate. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Martian dust is somewhat chemically distinct from the underlying soil, with a larger component of nanophase iron oxides responsible for its ochre hue.

“Martian dust is somewhat chemically distinct from the underlying soil, with a larger component of npOx responsible for its ochre hue (Morris et al., 2001; Berger et al., 2016).”

• cites Morris et al., 2001 sourceNot checked — no full text of the source
• cites Berger et al., 2016 sourcePartly supported

  The Results and Discussion report that Martian dust is compositionally similar to soil but enriched in Fe, S, and Cl; the Discussion also concludes that global dust is enriched in nanophase iron oxide (npOx). The cited paper does not say that npOx is responsible for the dust’s ochre hue. Page numbers are unavailable in our copy. (LLM, conf=0.85)

  Experimental — accuracy not yet measured

May combine two claims.

Soil major element chemistry and mineralogy are quite similar at the Spirit, Opportunity, and Curiosity landing sites, supporting the presence of a global basaltic soil.

“Soil major element chemistry and mineralogy are quite similar at the Spirit, Opportunity, and Curiosity landing sites (Yen et al., 2013; Ming and Morris, 2017), supporting the presence of a global basaltic soil that may be locally to regionally enriched in rarer evolved volcanic compositions (e.g., Christensen et al., 2005) or alteration phases (e.g., Squyres et al., 2008).”

• cites Yen et al., 2013Not checked — no full text of the source
• cites Ming and Morris, 2017Partly supported

  The Chemical Properties section (page not supplied) says basaltic soil at the Spirit, Opportunity, and Curiosity landing sites has similar composition, supporting the claim about chemistry and a widespread basaltic soil. It also notes differences in local basaltic mineralogies; the Mineralogical Properties section describes minerals observed by the rovers but does not establish that mineralogy is quite similar across all three sites. (LLM, conf=0.83)

  Experimental — accuracy not yet measured

May combine two claims.

The SAM instrument detected a broad H2O release in Rocknest starting at low temperatures, finding 2.0 ± 1.3 wt.% total evolved water averaged over four runs.

“the SAM instrument detected a broad H2O release in Rocknest starting at low temperatures, finding 2.0 ± 1.3 wt.% total evolved water averaged over four runs (Archer et al., 2014).”

• cites Archer et al., 2014 sourceSupported

Probably not a substantial claim: may not pass S3 (load-bearing).

Mastcam data in Figure 4 were reproduced from Fig. 5 in Wellington et al. (2017).

“Mastcam data (filled circles) were reproduced from Fig. 5 in Wellington et al. (2017)”

• cites Wellington et al. (2017) sourceSupported

Probably not a substantial claim: may not pass S3 (load-bearing).

Pike et al. (2011) reported that ~1 vol.% of Phoenix surface materials were <4 μm.

“Pike et al. (2011) reported that ~1 vol. % of the Phoenix surface materials were <4 µm”

• cites Pike et al. (2011) sourcePartly supported

  The Approach and Results section describes a cumulative-volume particle-size distribution for Phoenix soil, and the Discussion reports less than 0.05% by volume below 2 µm. The passages do not give a volume fraction below 4 µm, so they do not establish the claimed ~1 vol.%. (LLM, conf=0.78)

  Experimental — accuracy not yet measured

Probably not a substantial claim: may not pass S3 (load-bearing).

Ming and Morris (2017) estimate that 15-25 wt.% of typical soils should consist of clay-sized grains due to chemical alteration.

“Ming and Morris (2017) estimate that due to chemical alteration, 15-25 wt.% of typical soils should consist of clay-sized grains.”

• cites Ming and Morris (2017)Supported

Classified as probably not a substantial claim.

The calculated MGS-1 composition was weighted by the proportions in Table 1, with the actual crystal chemistries of martian silicates from Bish et al. (2013) and Morris et al. (2015).

“weighted by the proportions in Table 1, with the actual crystal chemistries of martian silicates from Bish et al. (2013) and Morris et al. (2015).”

• cites Bish et al. (2013) sourceSupported
• cites Morris et al. (2015)Not checked — no full text of the source

May combine two claims.

Upon heating and drying, sodium metasilicate forms a polymer network that acts as a binder, such that the resulting cobbles are solid and quite hard.

“Upon heating and drying, the sodium metasilicate forms a polymer network that acts as a binder, such that the resulting cobbles are solid and quite hard (Fig. 2c).”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Ferric sulfate and iron carbonate can be synthesized in amorphous form by evaporating appropriate solutions in vacuum, but they are prone to recrystallize in normal laboratory conditions.

“These species can be synthesized in amorphous form by evaporating appropriate solutions in vacuum, but they are prone to recrystallize in normal laboratory conditions.”

May combine two claims.

JSC Mars-1 has virtually none of the same minerals as actual Mars soil, and its volatile content (>20 wt.% H2O) is highly unrealistic.

“JSC Mars-1 is not recommended for these applications because it has virtually none of the same minerals as actual Mars soil, and its volatile content (>20 wt.% H2O) is highly unrealistic.”

May combine two claims.

The negative spectral slope at wavelengths >1000 nm in remote data is not as strong in the MGS-1 simulant, and the simulant is brighter.

“However, the negative spectral slope at wavelengths >1000 nm in the remote data is not as strong in the simulant, and the simulant is brighter.”

May combine two claims.

JSC Mars-1 has a significantly higher albedo than remote measurements, with strong H2O- and OH-related absorptions at 1400 and 1900 nm.

“JSC Mars-1 has a significantly higher albedo than the remote measurements, with strong H2O- and OHrelated absorptions at 1400 and 1900 nm.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The particle size distribution of simulants is highly adjustable through crushing and sieving.

“The particle size distribution of simulants is highly adjustable through crushing and sieving.”

May combine two claims.

SiO2, Al2O3, and SO3 in MGS-1 prototypes are much closer to Rocknest measured values and compare favorably to older martian simulants.

“Other elements such as SiO2, Al2O3, and SO3 are much closer to the measured values from Rocknest, and compare favorably to older martian simulants.”

May combine two claims.

MMS-1 and MMS-2 have even higher albedos than JSC Mars-1, and at shorter wavelengths are dominated by the signature of hematite.

“The MMS-1 and MMS-2 simulants from The Martian Garden company have even higher albedos than JSC-Mars 1, and at shorter wavelengths are dominated by the signature of hematite.”

Probably not a substantial claim: may not pass S3 (load-bearing).

In the prototype simulants, crystalline siderite was added.

“In the prototype simulants we added crystalline siderite.”

Probably not a substantial claim: may not pass S3 (load-bearing).

In the prototype simulants, crystalline iron (III) sulfate pentahydrate was added.

“In the prototype simulants we added crystalline iron (III) sulfate pentahydrate.”

Probably not a substantial claim: may not pass S4 (based).

There are apparent changes between MMS and MMS-1/2.

“Again, due to apparent changes between MMS and MMS-1/2, we do not recommend these simulants.”

Classified as probably not a substantial claim. May combine two claims.

The utility of JSC Mars-1, MMS, and their updated versions comes mostly from being fine-grained, roughly basaltic composition materials; this may be appropriate for certain uses that do not require high fidelity simulants, but inappropriate for others.

“The utility of these simulants (JSC Mars-1, MMS, and their updated versions) comes mostly from the fact that they are fine-grained, roughly basaltic composition materials: this may be appropriate for certain uses that do not require high fidelity simulants, but inappropriate for others.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

JSC Mars-1 is extremely hygroscopic, contains >20 wt.% H2O at ambient conditions, and is known to contain significant amounts of organic matter.

“JSC Mars-1 is extremely hygroscopic, contains >20 wt.% H2O at ambient conditions, and is known to contain significant amounts of organic matter as well.”

May combine two claims.

Magnetite, anhydrite and hematite were near the detection limit, but magnetite is important for magnetic properties, anhydrite for sulfur contents, and hematite for pigmenting properties.

“Magnetite, anhydrite and hematite were also near the detection limit, but magnetite is important for magnetic properties, anhydrite for sulfur contents, and hematite for pigmenting properties.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

MMS-2 is spiked with sulfates and other phases to resolve discrepancies in bulk chemistry, but its package composition confusingly lists both mineral percentages and wt.% oxides in the same table, summing them to 100%.

“As noted above, the MMS-2 simulant is spiked with sulfates and other phases to resolve discrepancies in bulk chemistry, but the composition on the package confusingly lists both mineral percentages and wt.% oxides in the same table, summing them to 100%.”

May combine two claims.

By starting with the correct mineral constituents, the derived properties should fall out of the final product, with adjustments made where necessary based on analyzing initial prototypes.

“By starting with the correct mineral constituents, the derived properties (geotechnical, spectral, chemical, etc.) should fall out of the final product, with adjustments made where necessary based on analyzing initial prototypes.”

May combine two claims.

The Martian Garden's MMS-1 and MMS-2 do not resemble the original MMS; the company is mining the highly altered red cinder material described by Beegle et al. (2007) instead of the original Saddleback Basalt.

“However, The Martian Garden company had no contact with the creators of MMS, and their simulants do not resemble the original version (compare Fig. 1d with Fig. 2 in Peters et al. (2008)). The company is instead mining the highly altered red cinder material described by Beegle et al. (2007) instead of the original Saddleback Basalt.”

• cites Peters et al. (2008) sourceNot checked — no full text of the source
• cites Beegle et al. (2007)Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Silicate minerals are likely shocked to various degrees on Mars, whereas the basic MGS-1 standard does not account for this.

“As well, silicate minerals are likely shocked to various degrees on Mars, whereas the basic MGS-1 standard does not account for this.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Other Mars simulants have been developed based on terrestrial basalts, natural weathering profiles, and commercial sand products.

“Other Mars simulants have also been developed based on terrestrial basalts, natural weathering profiles, and commercial sand products.”

May combine two claims.

MGS-1 is a new open standard designed as a high-fidelity mineralogical analog to global basaltic regolith on Mars, as represented by the Rocknest windblown deposit at Gale crater.

“Here, we describe the Mars Global Simulant (MGS-1), a new open standard designed as a high fidelity mineralogical analog to global basaltic regolith on Mars, as represented by the Rocknest windblown deposit at Gale crater.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Quantitative mineralogical analysis is not available for JSC Mars-1, MMS, MMS-1, or MMS-2, although this is not really feasible for JSC Mars-1 due to its mostly amorphous character.

“Quantitative mineralogical analysis is not available for either JSC Mars-1, MMS, MMS-1, or MMS-2, although this is not really feasible for JSC Mars-1 due to its mostly amorphous character.”

Probably not a substantial claim: may not pass S3 (load-bearing).

JSC Mars-1 was later reproduced as JSC Mars-1A by Orbitec when the original supply ran out.

“The most prominent Mars simulant is Johnson Space Center JSC Mars-1 (Allen et al., 1998), which was later reproduced as JSC Mars-1A by Orbitec when the original supply ran out.”

• cites Allen et al., 1998Not checked — no full text of the source

May combine two claims.

The amorphous component of Rocknest is deficient in SiO2, Al2O3, and CaO, and enriched in SO3 and H2O compared to the bulk soil.

“Dehouck et al. (2014) and Morris et al. (2015) isolated the elemental chemistry of the amorphous component using a mass balance approach (Table 2), showing that it is deficient in SiO2, Al2O3, and CaO, and enriched in SO3 and H2O compared to the bulk soil.”

• cites Dehouck et al. (2014) sourceNot checked — no full text of the source
• cites Morris et al. (2015)Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

Mojave Mars (MMS) is not currently available outside of NASA.

“The other notable Mars simulant is Mojave Mars (MMS) (Peters et al., 2008), that is not currently available outside of NASA.”

• cites Peters et al., 2008 sourceNot checked — no full text of the source

May combine two claims.

The root MGS-1 standard does not include crystalline nitrate and perchlorate salts, although some initial prototypes designed for agricultural studies did include them.

“We included crystalline nitrate and perchlorate salts in some of our initial prototypes designed for agricultural studies, but do not include them in the root MGS-1 standard.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Martian soils have been examined in-situ at seven locations by landers and rovers, with supplemental information from orbital remote sensing.

“Martian soils have been examined in-situ at seven locations by landers and rovers, with supplemental information from orbital remote sensing.”

May combine two claims.

Previous simulants often sacrificed accuracy for convenience, had poor documentation, and their resulting products have been assumed to be appropriate for all types of research.

“Previous simulants often sacrificed accuracy for convenience, had poor documentation, and the resulting products have been assumed to be appropriate for all types of research.”

• cites Taylor et al., 2016 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Mars Global is not meant to be a perfect standard, and there are almost certainly trace mineral species present in martian soil that are not represented in MGS-1, including phosphates, sulfides, chromates, oxalates, and other rare species.

“Mars Global is not meant to be a perfect standard for simulants (if such a thing exists), and there are almost certainly trace mineral species present in martian soil that aren't represented in MGS-1: these could include phosphates, sulfides, chromates, oxalates, and other rare species.”

Probably not a substantial claim: may not pass S4 (based).

These other Mars simulants have not yet been widely distributed or adopted.

“These simulants have not yet been widely distributed or adopted.”

May combine two claims.

Simulants designed to match bulk chemistry might provide a close match to readily available measurements, but a simulant could be designed from infinite combinations of random compounds to reproduce the bulk chemistry of a reference material without having any of the right minerals inside it.

“Simulants designed to match bulk chemistry might provide a close match to more readily available measurements (from Alpha Particle X-ray Spectrometer instruments, for example), but a simulant could be designed from infinite combinations of random compounds to reproduce the bulk chemistry of a reference material without having any of the right minerals inside of it.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

The plagioclase, pyroxene and olivine added separately in MGS-1 prototypes could also be added in the form of basalt or ultramafic rocks provided the mineral proportions are accurate.

“While we have chosen to add the plagioclase, pyroxene and olivine separately in our prototypes, they could also be added in the form of basalt or ultramafic rocks provided the mineral proportions are accurate.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Additional phases may be present in an amorphous or poorly-crystalline state in martian soil.

“Additional phases may be present in an amorphous or poorly-crystalline state, as discussed above.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Soils at the Pathfinder landing site had an estimated bulk density of 1.07-1.64 g/cm3.

“soils at the Pathfinder landing site had an estimated bulk density of 1.07-1.64/cm 3 (Moore et al., 1999)”

• cites Moore et al., 1999 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

The initial physical properties measurements in this study are limited.

“As well, in the prototypes we did not control for detailed aspects like particle shape that can be important in influencing geotechnical properties, and our initial physical properties measurements in this study are limited.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

The other phases in the MGS-1 standard are available in relatively pure forms from either natural sources or as synthetic chemical supplies.

“The other phases in the MGS-1 standard are available in relatively pure forms from either natural sources or as synthetic chemical supplies.”

May combine two claims.

TGA data are not available for MMS-1 or MMS-2, but judging from their spectral properties these simulants have significant water contents, possibly on par with JSC Mars-1.

“TGA data are not available for MMS-1 or MMS-2, but judging from their spectral properties (Fig. 4) these simulants have significant water contents, possibly on par with JSC Mars-1.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The observed spectral differences between MGS-1 and Mars may be caused by a combination of differences in crystal chemistry, specific amorphous compounds present on Mars, shock darkening, and ambient laboratory measurement conditions.

“These observed differences may be caused by a combination of differences in crystal chemistry, the specific amorphous compounds present on Mars, shock darkening, as well as the fact that the simulant spectra were measured at ambient laboratory conditions.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Clay-rich Noachian regolith, or perchlorate and nitrate-bearing agricultural soils can be created by adding desired additional components to the root simulant.

“For example, clay-rich Noachian regolith, or perchlorate and nitrate-bearing agricultural soils can be created by adding the desired additional components to the root simulant.”

Probably not a substantial claim: may not pass S4 (based).

In the past, simulant production has followed a predictable lifecycle: need arose, a NASA center or private company produced an initial large batch, then the batch ran out or interest faded and the simulant was discarded.

“In the past, simulant production has followed a now predictable lifecycle: the need for a specific simulant arose, a NASA center or private company produced an initial large batch of the simulant, then eventually the batch ran out, or national interest in a given planetary body faded and the simulant was discarded.”

Probably not a substantial claim: may not pass S4 (based).

The geotechnical properties of actual martian regolith are poorly constrained compared to returned lunar regolith that has been studied extensively on Earth.

“However, the geotechnical properties of actual martian regolith are poorly constrained compared to returned lunar regolith that has been studied extensively on Earth.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

NASA developed the concept of 'root' and 'branch' simulants for the Moon, where the root is a basic, well-characterized version of the simulant.

“NASA developed the concept of 'root' and 'branch' simulants for the Moon, where the root is a basic, well-characterized version of the simulant.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Using more accurate Fe- and Ca-rich silicate compositions would result in higher densities for MGS-1 simulants.

“Using more accurate Fe- and Ca-rich silicate compositions would result in higher densities.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Drift material at the Viking 1 landing site had an estimated bulk density of 1.15±0.15 g/cm3.

“drift material at the Viking 1 landing site had an estimated bulk density of 1.15±0.15 g/cm 3 (Moore and Jakosky, 1989)”

• cites Moore and Jakosky, 1989 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Natural, high-purity sources of fayalitic olivine, pigeonite, and unweathered calcic plagioclase are rare on Earth, but efforts to source them in the future will greatly improve the bulk chemistry of the simulants.

“Natural, high-purity sources of fayalitic olivine, pigeonite, and unweathered calcic plagioclase are rare on Earth, but efforts to source them in the future will greatly improve the bulk chemistry of the simulants.”

May combine two claims.

There is no batch of MGS-1 to run out, but a general standard to follow.

“In this way, there is no batch of MGS-1 to run out, but a general standard to follow.”

Probably not a substantial claim: may not pass S3 (load-bearing).

A group at the Johnson Space Center is also developing a Rocknest-based version of the MMS simulant to be used for ISRU development.

“Indeed, a group at the Johnson Space Center is also developing a Rocknest-based version of the MMS simulant to be used for ISRU development (Archer et al., 2018).”

• cites Archer et al., 2018Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

None of the spectra in Figure 4 have been offset or scaled.

“None of the spectra have been offset or scaled.”

Probably not a substantial claim: may not pass S3 (load-bearing).

MMS has recently been augmented further to achieve even more realistic volatile release patterns.

“MMS has recently been augmented further to achieve even more realistic volatile release patterns (Archer et al., 2018).”

• cites Archer et al., 2018Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

The significant and unrealistic water contents of JSC Mars-1 were cited as a motivating factor in developing the original MMS simulant.

“The significant and unrealistic water contents of JSC Mars-1 were cited as a motivating factor in developing the original MMS simulant (Peters et al., 2008)”

• cites Peters et al., 2008 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing). The quote only partly states this claim.

The prototype MGS-1 composition values in Table 2 are averages of 5 measurements.

“Average of 5 measurements.”

Classified as probably not a substantial claim.

Allen et al. (1998) reported that JSC Mars-1 lost 21.1 wt.% (mostly water) when heated to 600 °C.

“Allen et al. (1998) reported that JSC Mars-1 lost 21.1 wt.% (mostly water) when heated to 600 °C”

• cites Allen et al. (1998)Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Sourcing a pre-existing, unweathered olivine-rich basalt or a combination of unweathered ultramafic rocks presents its own set of challenges and usually requires a large capital investment if the right material is not already being mined.

“However, sourcing this kind of material presents its own set of challenges, and usually requires a large capital investment if the right material is not already being mined.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Source minerals have been crushed into powders and analyzed by XRD, VNIR spectroscopy, and X-ray Fluorescence to verify their identity and detect any contaminants present.

“These minerals have been crushed into powders and analyzed by XRD, VNIR spectroscopy, and X-ray Fluorescence (XRF) to verify their identity and detect any contaminants present.”

May combine two claims.

The TEGA instrument did not detect low temperature water release in soil samples at the Phoenix landing site, but did detect a minor H2O release starting at 295 °C and a major release starting at 735 °C.

“The TEGA instrument did not a detect low temperature water release in soil samples at the Phoenix landing site (Smith et al., 2009), but did detect a minor H2O release starting at 295 °C and a major release starting at 735 °C.”

• cites Smith et al., 2009 sourceNot checked — no full text of the source

Classified as probably not a substantial claim. May combine two claims.

The prototype simulants were analyzed using a variety of imaging techniques and bulk analyses, and results were compared to relevant datasets from various orbital and in-situ spacecraft measurements as appropriate.

“The prototype simulants were analyzed using a variety of imaging techniques and bulk analyses. Results from these analyses were compared to relevant datasets from various orbital and in-situ spacecraft measurements as appropriate.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The differences between the MGS-1 based simulant and Rocknest could be due to hygroscopicity in a humid terrestrial atmosphere, and the exact nature of the amorphous component in Rocknest is probably key to understanding the unique water release patterns measured by SAM.

“The differences between the MGS-1 based simulant and Rocknest could be due to hygroscopicity in a humid terrestrial atmosphere, and the exact nature of the amorphous component in Rocknest is probably key to understanding the unique water release patterns measured by SAM (Archer et al., 2018).”

• cites Archer et al., 2018Not checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

Mojave Mars Simulant was developed specifically for geotechnical applications.

“Mojave Mars Simulant was developed specifically for geotechnical applications (Peters et al. 2008)”

• cites Peters et al. 2008 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

MGS-1 will benefit from the same root/branch scheme, where the recipe in Table 1 forms the basic root, and various branches can be created either by the authors or others.

“MGS-1 will benefit from the same scheme, where the recipe in Table 1 forms the basic root, and various branches can be created either by us or others.”

• AssumptionRests on an assumption: The mineral recipe in Table 1 accurately represents the mineralogy of average basaltic regolith on Mars.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Peters et al. (2008) report that MMS lost 1.7 wt.% by 100 °C and 7.2 wt.% by 500 °C.

“Peters et al. (2008) report that MMS lost 1.7 wt.% by 100 °C and 7.2 wt.% by 500 °C.”

• cites Peters et al. (2008) sourceNot checked — no full text of the source

May combine two claims.

Unlike previous simulants sourced from landscaping material, Mars Global is meant to be assembled ab initio from pure components to provide an accurate match to the mineralogy of martian regolith.

“Unlike previous simulants sourced from landscaping material, Mars Global is meant to be assembled ab initio from pure components to provide an accurate match to the mineralogy of martian regolith.”

• AssumptionRests on an assumption: Rocknest windblown soil is representative of average basaltic martian regolith for the purpose of defining a global Mars simulant standard.
• AssumptionRests on an assumption: The mineral recipe in Table 1 accurately represents the mineralogy of average basaltic regolith on Mars.