By COLIN M. STEWART
By COLIN M. STEWART
Tribune-Herald staff writer
NASA’s $2.5 billion mission to Mars aboard the rover Curiosity traveled 352 million miles through the deep cold of space for eight months to deposit itself on the surface of an alien world.
Now, after all that, scientists have learned that the rover sits atop soil one might find right here on the flanks of Mauna Kea.
In a press release issued Tuesday, NASA’s Jet Propulsion Laboratory reported that the rover’s first Martian soil sample studies revealed minerals similar to the weathered basaltic soils of volcanic origins found in Hawaii.
Of course, such results aren’t really a surprise, said Ken Hon, head of the University of Hawaii at Hilo’s geology department. Instead, these experiments serve to fill in gaps and solidify data provided by prior explorations into the red planet’s geologic history.
“They’re finding that the same range of compositions that we see here on our island exist on Mars,” he said. “They had already found most of that through remote sensing, but they didn’t have the same sophisticated instruments we have on (Curiosity). Now we have the hard numbers.”
Mauna Kea, Mauna Loa and Kilauea serve as the best training grounds for missions to Mars because of the similarity of their formations and mineral compositions to what scientists believe they will find on Mars, he said.
“Our island is the preferred place to use for a Mars analogue for a couple of reasons,” Hon said.
First, are the lava fields here on the island. While there are lava fields on the mainland, they are susceptible to accumulating rock dust from other formations from long distances away that are not representative of the types of volcanic environments expected on Mars, he said.
Meanwhile, Mauna Kea provides a lot of windblown sand and dust from glaciation that is very similar to the sand dunes observed on Mars.
Lastly, there’s simply the question of scale.
“Mars has the largest shield volcano in the solar system, and we have the largest shield volcano on Earth,” he said. “Hawaii really is an excellent place to do this. Hawaii Island has long been seen as THE place to look to understand the geology of Mars.”
According to the NASA release, Curiosity utilized its Chemistry and Mineralogy instrument, or CheMin, to obtain the results from a sample collected on Oct. 15. It uses X-ray diffraction, a standard practice for geologists on Earth, although they use much larger laboratory instruments. The method provides more accurate identifications of minerals than any method previously used on Mars. X-ray diffraction reads minerals’ internal structure by recording how their crystals distinctively interact with X-rays.
Innovations pioneered by NASA’s Ames Research Center in Moffett Field, Calif., led to an X-ray diffraction instrument compact enough to fit inside the rover. Those advances have resulted in other applications on Earth, including “compact and portable X-ray diffraction equipment for oil and gas exploration, analysis of archaeological objects and screening of counterfeit pharmaceuticals,”the release stated.
“Our team is elated with these first results from our instrument,” said David Blake, principal investigator for CheMin at Ames. “They heighten our anticipation for future CheMin analyses in the months and miles ahead for Curiosity.”
Hon said that he had the opportunity to work in the field with Blake and use the new X-ray diffraction equipment, and he believes it represents a significant leap forward for the state of the art.
“This thing is now the size of a briefcase, down from the size of a refrigerator,” he said. “It’s a totally new and novel way of looking at a sample.”
The Martian samples were taken from a patch of dust and sand that the Curiosity team has named “Rocknest.”
“So far, the materials Curiosity has analyzed are consistent with our initial ideas of the deposits in Gale Crater recording a transition through time from a wet to dry environment,” said David Bish, CheMin co-investigator with Indiana University in Bloomington, Ind. “The ancient rocks, such as the conglomerates, suggest flowing water, while the minerals in the younger soil are consistent with limited interaction with water.”
Among the minerals discovered in the deposit were feldspar, pyroxene and olivine. Roughly half the soil was categorized as non-crystalline material, such as volcanic glass or products from weathering of the glass, Bish said.
The Mars Science Laboratory Project’s two-year mission is focused on using Curiosity’s collection of 10 different instruments to discover whether areas in Mars’ Gale Crater ever offered environmental conditions favorable to simple lifeforms.
For more information on the project, visit www.nasa.gov/msl.
Email Colin M. Stewart at cstewart@hawaiitribune-herald.com.