Readers discuss meteorite identification, fly factories and more

Magnetic muck-ups

A study of fragments from a Martian meteorite shows that the common practice of using magnets to identify meteorites can overwrite records of magnetic fields stored within the space rocks, Katherine Kornei reported in “Searching for meteorites? Ditch the magnets” (SN: 6/3/23, p. 5).

Reader C. R. Prahl asked how scientists can know precisely a meteorite’s source.

Scientists can determine a meteorite’s origins by looking at the space rock’s chemical makeup, Kornei says. As rocks form, tiny air bubbles often get trapped within them. Those air pockets sometimes chemically look nothing like Earth’s atmosphere. For example, the chemical composition of the air pockets in the meteorite fragments used in this study was a great match for Mars’ atmosphere.