Quirks & Quarks

Your rooftop could be sprinkled with cosmic star dust

A jazz musician moonlighting as an amateur scientist discovered cosmic dust falls all around us.
Particles of dust, some cosmic, some made right here on Earth (Jon Larsen)

This segment originally aired on September 29th, 2017

The hunt for micrometeorites

Eight years ago, Jon Larsen, a jazz musician from Norway, was sitting at a table when a shiny speck of metallic dust landed in front of him. That was enough to spark his interest and to start his search for more particles, which he suspected could be extra terrestrial in origin. Mr. Larsen started contacting different scientists who study cosmic dust, otherwise known as micrometeorites, but the only one who'd take him seriously, after Mr. Larsen kept persisting, was Dr. Matthew Genge from Imperial College London. Together they were able to prove that many of the dust particles Mr. Larsen had found were, in fact, micrometeorites. Now Mr. Larsen sharing his discoveries in a new book called, In Search of Stardust - Amazing Micrometeorites and Their Terrestrial Imposters.

Why this discovery is important

Until Mr. Larsen and Dr. Genge published their paper in the journal Geology about their discovery of urban micrometeorites, nobody thought it would be possible to find them on urban rooftops. Historically, most micrometeorites have been found in places like Antarctica. Since many of the roofs where Mr. Larsen made his discoveries were new, this discovery shows that fresh micrometeorites fall down to Earth all the time.

What micrometeorites can teach us

The main thing we can learn from most micrometeorites, because they're mostly samples of asteroids, which date back 4.5 billion years, is they provide a unique record into the formation of our early solar system. 

The micrometeorite hunter Jon Larsen finds cosmic dust on roofs all over the world. (Jon Laren)
These small beauties were found in the ice on the South Pole, but similar spherules are in fact falling down upon us, everywhere, at all times. (Jon Larsen)
This micrometeorite was found on a roof in Oslo. It is a porphyritic stone with a relatively large metal bead in the front. (Jan Braly Kihle/Jon Larsen)
A completely melted amorph glass micrometeorite with a metal bead in the front. (Jon Larsen)
This is what a micrometeorite looks like under a scanning electron microscope. (Jon Larsen)
These Earth-made particles are made from mineral wool, which is used worldwide as insulation. (Jon Larsen)
These Earth-made particles are the product of fireworks. (Jon Larsen)
These Earth-made particles are grains of roof tiles and shingles where the dust was found. (Jon Larsen)
This was the moment of truth for Jon Larsen when he confirmed some of his dust samples were extraterrestrial in origin. (Jon Larsen)