JSC Mars-1 and JSC Mars-1A After the
Viking landers and the
Mars Pathfinder's rover landed on Mars, the onboard instruments were used to determine the properties of the
Martian soil at the landing sites. The studies of the
Martian soil properties led to the development of JSC Mars-1 Martian regolith simulant at NASA's
Johnson Space Center in 1998. It contained
palagonitic tephra with a
particle size fraction of less than 1 millimeter. The palagonitic tephra, which is
glassy volcanic ash altered at low temperature, was mined from a quarry at the Pu'u Nene
cinder cone. The studies of the cone, which is located between
Mauna Loa and
Mauna Kea in
Hawaii, indicate that the tephra is a close spectral analog to the bright regions of Mars. When the original supply of JSC Mars-1 ran out, there were needs for additional material. NASA's
Marshall Space Flight Center contracted Orbital Technologies Corporation to supply 16
metric tons of lunar and Martian simulants. The company also made an additional eight tons of Martian simulant available for other interested parties to purchase. However, as of 2017 JSC Mars-1A is no longer available. After milling to reduce its particle size, JSC Mars-1A can
geopolymerize in alkaline solutions forming a solid material. Tests show that the maximum
compressive and
flexural strength of the 'martian' geopolymer is comparable to that of common clay bricks.
MMS MMS or Mojave Mars Simulant was developed in 2007 to address some issues with JSC Mars-1. While JSC Mars-1 did simulate the color of Martian regolith, it performed poorly in many qualities, including its
hygroscopic tendencies—it had undergone
weathering that attracts water, making it more
clay-like. MMS, however, was hygroscopically inert due to minimal weathering and the way it was crushed, which allowed it to better simulate that feature of Martian regolith, among others. MMS was found naturally as whole rocks in a volcanic formation near the town of
Boron, California, in the western
Mojave Desert. After crushing,
basalt sands were processed and graded into particular sizes, MMS Coarse and MMS Fine. MMS Dust consists of smaller basalt particles matching the particle size distribution of
Martian dust. A separate volcanic event created red-colored
cinder which is mined and crushed to create MMS Cinder. It is based on the Rocknest soil in
Gale crater on Mars that has been analyzed extensively by the
NASA Curiosity rover. MGS-1 is produced by mixing pure minerals together in accurate proportions, with a realistic particle size distribution. The simulant is available from the not-for-profit Exolith Lab at the
University of Central Florida. MGS-1 does not include
perchlorates by default, so it cannot be used to test the effects of that aspect of the Martian regolith. However, end users can spike the material with perchlorate salts or other superoxide species. ==Health risks==