This week I wrote about the oldest solid material identified on Earth: 7 billion-year-old stardust pried out of a fallen meteorite. Those stardust grains are very tiny: Just micrometers across, they're too small to see with the naked eye.
But these precious pieces had to be shipped from laboratory to laboratory over the course of a study published Monday in the Proceedings of the National Academy of Sciences. They moved from the University of Chicago (where researchers extracted dust from the meteorite) to Washington University in St. Louis (where an electron microscope identified the minerals) to ETH Zurich, a university in Switzerland (to measure neon gas inside the stardust).
Researchers don't like to transport loose stardust, said cosmochemist Philipp Heck, of Chicago's Field Museum, because the risk of losing them is too high.
So how does the dust travel? With a little help from gold.
"We always try to press them into soft gold, so they stay in place," Heck said. Researchers use hydraulic micro-manipulators, with needle tips, to maneuver the individual grains. Once prepped, the grains are squished into gold mounts. Then the mounts are sealed in plastic bags to be hand-carried to new labs.
Or the dust grains, which once floated through space for millions and millions of years, and are now snug in gold, are popped in the mail. "We sometimes FedEx them," Heck said. "Touch wood — we haven't ever lost a mount."