Collection helps answer questions about solar system evolution
Nearly 570 meteorite samples collected during a two-month Antarctic expedition arrived at NASA’s Johnson Space Center on April 14 to be curated for distribution to scientists around the world, helping us answer questions about the evolution of the solar system, including the role that water and organic compounds have in its formation.
Braving temperatures as cold as minus 10 degrees Fahrenheit, a team of eight scientists, including NASA’s own Astromaterials Curation Chief Cindy Evans, spent time in the frozen landscape as part of the Antarctic Search for Meteorites (ANSMET), a 40-year program that has helped reveal information about asteroids, other bodies of our solar system and the Red Planet, which will assist NASA on its Journey to Mars.
“Meteorites are currently the only way to acquire samples from Mars, as well as new samples of the moon that are different from—and originated far from—the Apollo landing sites, as well as a variety of asteroid bodies,” Evans said. “The ANSMET program has gathered more than 21,000 meteorites since 1976, a diverse collection including material from both the surface and interior of these bodies.”
Understanding the solar system
As NASA’s home for astromaterial curation, JSC curators from the Astromaterials Research and Exploration Science (ARES) Division
received the meteorites from the field; provided the initial processing and early descriptions of the samples; and collaborated with the Smithsonian Institution for characterization so that the samples can be announced and listed in the database and discoverable by scientists.
“I think of the meteorites as pieces of a huge solar system jigsaw puzzle that planetary scientists are trying to put together to discover the picture of solar system evolution,” Evans said. “The meteorites collected give us important clues about the early solar system, but even the thousands of meteorites recovered over the years represent a tiny part of the larger puzzle—including a find in the 1990s that produced evidence that sparked a vigorous debate about whether life could have existed on Mars more than 3.6 billion years ago.”
Kevin Righter, ARES meteorite lab curator, relayed that some of the samples provide ground truth for robotic missions to asteroids.
“We have meteorite samples believed to be from the asteroid Vesta that was visited by NASA’s Dawn Spacecraft,” Righter said. “We also have recovered carbonaceous chondrites, or primitive meteorites, that provide important data for the Japan Aerospace Exploration Agency’s Hayabusa 2 Spacecraft already headed for a carbonaceous asteroid and NASA’s 2016 OSIRIS REx mission that will travel to a near-Earth asteroid called Bennu and bring a small sample back to Earth for study.”
As engineers and scientists around the country work hard to develop the technologies astronauts will use to one day live and work on Mars and safely return home from the next giant leap for humanity, the meteorites provide critical data that enable engineers to build the right technologies.
“Scientists have learned to tease amazing information from these samples, including information about water in the inner solar system, organic compounds (including some of the building blocks for life) and more,” Righter said. “Most of the Earth’s surface rocks are much younger than the meteorites, so these samples are critical to understanding the evolution of the Earth, in addition to conditions on other bodies that will one day be explored by our own astronauts.”
The Antarctic mission
In the field, the ANSMET team executes planned sweeps of the targeted blue ice fields, similar to a search-and-rescue mission. If someone finds a meteorite, that person stops and flags the entire team over to collect the sample and the associated data.
“I was the photographer, so I photographed each sample with its associated field tag number,” Evans said. “The sampling team pulls out the sampling gear (an aluminum field tag printed at JSC, Teflon bag, foil, if appropriate, and tongs).”
Evans noted that the samples are kept as pristine as possible (not touched by hands or equipment that hasn’t been cleaned), placed in the bag and secured for transport back to Houston. The samples are kept frozen so that they can be warmed and thawed out in a controlled way, under a nitrogen atmosphere, keeping water and oxygen away from them.
“Other data is also collected at the time a meteorite is picked up, including the GPS coordinates, a brief field description and any other key information about the sample (percent fusion crust, notes about the environment),” Evans said. “Over the years, the ANSMET program has kept maps with locations of where meteorites are found, the field conditions, terrestrial rocks and more.”
Scientists spent five weeks in the field and a little more than two weeks beforehand training at McMurdo Station, a U.S. research facility, to collect gear, train and wait for flights to the field.
Evans’ participation marks the 22nd ARES staff member, in addition to six NASA astronauts, who have participated in the ANSMET program since 1978.
“It was an honor to be able to collect extraterrestrial samples for the global planetary science community to study,” Evans said. “The experience provides some insight into how humans might conduct future exploration activities on a planetary body in the near future.”
To learn more about Johnson Space Center’s meteorite collection, visit: http://curator.jsc.nasa.gov/antmet/index.cfm
For more information about the ANSMET program, visit: http://caslabs.case.edu/ansmet/
ANSMET 2015-2016 team member Cindy Evans points to the ANSMET property stamp on the frozen sample containers. Donna Castillo from the Astromaterials Research and Exploration Division facilitates the delivery to JSC while Antarctic Meteorite Curator Kevin Righter is happy to have the meteorites come home. Image Credit: NASA/James Blair
NASA Johnson Space Center
ANSMET team selfie from the North Miller Range, Antarctica. The team, from left: Ellen Crapster-Pregont, Cindy Evans, Nina Lanza, Constantine Tsang, Morgen Martinez, Jim Karner, Brian Rougeux and John Schutt had just finished a long day of hunting meteorites on the blue ice fields. Image Credit: NASA
Blue ice field in the Miller Range, near the edge of a moraine. Moraines are piles of rocks deposited along the edge of a glacier. Often they are good hunting grounds for meteorites, but the samples from space are mixed in with lots of terrestrial rocks. Image Credit: NASA/Cindy Evans
Aboard snow machines, the team traverses a pass toward the blue ice field in the distance. Image Credit: NASA/Cindy Evans
A field selfie using the reflection in Crapster-Pregont’s shiny ski goggles. Image Credit: NASA/Cindy Evans
Schutt, a mountaineer, examines a new find, holding the sample with clean tongs while the rest of the team prepares the sampling tag and bag. Image Credit: NASA/Cindy Evans
Striking gold—er, black. A meteorite in the rough. The black fusion crust, formed when the sample heated up in the Earth’s atmosphere as it was falling to the ground, helps the team spot samples in the field. Image Credit: NASA/Cindy Evans
From left, Evans, Donna Castillo and Righter greet the delivery driver and meteorites at JSC. After a long, frozen journey via refrigerated cargo ships from McMurdo Station, Antarctica, the samples are home in the Meteorite Processing Lab in Building 31. Image Credit: NASA/James Blair
Curation team members unload the new meteorite delivery into the freezers in the Meteorite Processing Lab. Ann Kascak, left, hands the samples to Evans. Image Credit: NASA/James Blair