Tiny grains of alien material in meteorites point to origins in other stars

You are made of star stuff.

Carl Sagan said this in his series Cosmos, and it’s literally true. We know the early Universe only had hydrogen and helium (and a soupçon of lithium) in it, and all the heavier elements — carbon, oxygen, phosphorus, and more — were made in stars. These were then ejected into space, eventually making their way into you (some steps may have been skipped here for brevity).

We’ve known for a while that these elements were created in many different stars. The Sun formed...