Micrometeorites are exceptionally small pieces of cosmic dust that have landed on a planet. These magnificently beautiful particles can be classified into different types based on their composition. Another way to differentiate between different micrometeorites is by size. Some particles are so tiny that powerful microscopes struggle to make out their details. Others, however are very large; These are the giants.
In this post, I’m delighted to present the first giant micrometeorite I ever found, NMM 500.
This wonderful barred olivine (BO) type micrometeorite measures just over 0.5 mm. It has no visible metal and very few small magnetite “Christmas tree” crystals on the surface. Perhaps its parent body in space was low on iron? This large aerodynamic particle is oriented (front is pictured up) and shows no signs of weathering. Its pristine state indicates it was fresh as a daisy when it was found in the rain gutter of Nesodden Skole, Akershus, Norway, in December 2015.
At that time it was still very controversial to suggest it was possible to identify micrometeorites by visual appearance alone. While the value of analysis cannot be understated, the idea that analysis was the only method of confirmation has since been dismissed, largely due to my work.
I hope you enjoyed learning about NMM 500! To this day, my first giant remains one of my favorites.