Why do we recover more meteorites?

Recovering a meteorite using sterilized tongs.

ANSMET has been collecting meteorites from the Antarctic blue ice fields for nearly 40 years, and this year’s team is really excited to contribute to ANSMET’s long and successful record with both lots of meteorites and a wide variety of meteorite types. Over the years, more than 20,000 meteorites have been recovered. One FAQ is “why do we need more meteorites? Isn’t 20,000 enough?” We have many answers to this question (more than I can address in one nightly blog), but here are a couple of reasons we keep recovering more meteorites.

First, we recover all the meteorites we find, so the collection is incredibly diverse – we have samples from hundreds of different asteroid bodies, including both the surface and the interior of these bodies (like the pallasite sample we collected last week). We have samples of very primitive materials that give us clues about the very early history of the solar system, including the Earth. In fact, 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. And, the collection includes our ONLY samples from the surface of Mars, and samples from the Moon that are different from and originated far from the Apollo landing sites. Some of the samples provide ground truth for robotic missions to asteroids: we have meteorite samples believed to be from asteroid Vesta that was visited by the Dawn spacecraft, the HEDs we’ve mentioned before. We also have recovered carbonaceous chondrites – primitive meteorites that contain carbon and carbon-bearing molecules – that provide important data for JAXA’s Hayabusa 2 spacecraft already headed for a carbonaceous asteroid, and NASA’s 2016 OSIRIS REX mission. In addition to providing samples from diverse solar system bodies, meteorite research is robust! Every year many hundreds of samples from the ANSMET collection are sent out to hundreds of scientists and planetary science students from around the world. Since the meteorites are our only samples from the asteroid belt (and Mars and parts of the Moon, for that matter), sample 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. 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. The main asteroid belt (the source of most of our meteorites) contains myriad asteroids. The ANSMET meteorites give us important clues about the early solar system, but even the thousands of meteorites recovered over the years represent a tiny, tiny part of the larger puzzle. We still have lots to learn! Look for future posts about what we are learning from ANSMET meteorites by my sample scientist colleagues.

– posted by Cindy, South Miller Range, Antarctica, 8 January 2016 (minor editing by RPH)

Cindy goes face to the ice searching for meteorites in a wind row. No meteorite, no matter how small, will escape her gaze. Who knows what unique samples she might find with her patented technique?

-An editorial note from RPH:  There’s some subtext here worth mentioning. Many of our blog readers conduct research on meteorites, and to them the value of the specimens may seem obvious. Cindy comes to us from the mission side of NASA; she has worked behind the scenes in Astromaterials at JSC for a long time from the sample management / curation / analysis angle, and is particularly interested in relationship of planetary samples to human exploration. Given that NASA supports a very broad spectrum of activities on a limited budget,  it make me happy when Cindy (or anyone from a different part of NASA) so clearly  “gets”  what we do. 

That said,  let me suggest that Hayabusa 2 and OSIRIS-REx are supporting ANSMET’s mission rather than vice-versa……….