Tell me you didn’t read the article without telling me…

Stars forged nearly all of the elements of the Universe. Many of the atoms that make up our bodies were themselves made inside of the core of a star somewhere else. That’s because the high pressures and temperatures can fuse lightweight atomic nuclei into heavier elements.

“The core is extremely hot, and then you go out in the atmosphere, it’s cool enough so that gas can form and aggregate into tiny grains,” Nguyen says.

Think of these little grains as cosmic dust motes. Sometimes the star that formed these grains would explode, blowing them across the galaxy like dandelion seeds. Other times they would drift away on their own — traveling on the stellar wind into deep space.

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[Ann Nguyen, a cosmochemist at NASA’s Johnson Space Center] says the grains look different than the material from our own solar system, because different stars leave different nuclear signatures in the atoms.

“It kind of lights up like a Christmas tree light,” she says. “Their isotopic signatures are just so different than the material that formed in our solar system or got homogenized in the solar system.”

tl;dr: Heavy elements that need to be produced before planetary accretion were found in minute quantities coating an asteroid.