I am a father, a husband, a veteran, and an amateur scientist. I've always had an interest in meteorites and I also consider myself a skeptic. Those two interests met each other head on when I first started learning about micrometeorites. There is a lot of misinformation online about micrometeorites and how to find them. At first I was also mislead, searching for anything magnetic from my rooftop suspecting that it was of extraterrestrial origin and then I learned micrometeorites were spherical. Both things are true, micrometeorites are magnetic and spherical but not the whole story and both of those things don't have to be the case. Then I found Jon Larsen's book and his Facebook page, there he taught me that in order to find micrometeorites you need to know what to look for but also what to discard. One of my main goals is to help people find actual micrometeorites and break down the misconception that anything small, magnetic, and spherical is automatically from space.
Long before I knew anything about micrometeorites I joined the Army. This was right after high school in 2001 and I was actually in basic training during 9/11, this event altered my life forever (as well as many others). While in the Army I did two tours, one in Afghanistan and one in Iraq. After I got out of the Army in 2005 I moved from Ft. Campbell, Tennessee to Minneapolis, Minnesota and started school right away. I have a degree in architecture but my heart has always been with the sciences. While not using my Architectural degree I continued to work and to go to school, I have basically been a student ever since I got out of the Army. I studied Physics and Astronomy and now I am currently studying Chemical Engineering while being a stay at home dad. Life has been changing quickly the last few years, getting married, having a son, and now I hope to contribute somehow to the scientific community with my research on micrometeorites.
This is the type that someone just starting to look for micrometeorites is most likely to find, and an added bonus when they have a iron/nickel bead that was trying to excape.
Although this micrometeorite may look smooth and shiny the closer we look with a Scanning Electron Microscope we will see that there are tiny crystalline structures that cover the surface. It is not the most common type of MM but keep an eye out for this type as well.
There are many variations of the Porphyritic micrometeorite but the one imaged here is one of my favorites. You can see some beautiful Olivine crystals on this one.
At high enough temperatures (around 2000 C) while entering the atmosphere micrometeorites can become glassy like the one pictured here.
Unmelted micrometeorites entered the atmosphere at a speed and angle that allowed them to keep their original form without melting.
Iron micrometeorites are extremely rare! Here is the 3rd urban I-type ever found.
1. The first thing I do is look for suitable roofs, flat, old, vinyl roofs. I do this by looking on google maps and searching for either black or white roofs because that usually means they are vinyl. Then I'll email the owner and ask for permission to search for stardust. Most will say no but all you need is one yes.
2. Once I get permission to access the roof I start out by looking for the areas that I want to pay close attention to. These spots include lower areas that have accumulated dirt and debris and the areas around any drainage. Water from rainfall or melting snow will carry the MMs to drainage and lower areas of the roof.
3. I use a powerful magnet wrapped tight in a zip-lock bag and a dustpan brush to sweep up the loose dirt and I hover the magnet over the material picking up anything magnetic. I then transfer all of the material I collect into a "mother bag" to bring home for cleaning. I cover as much of the roof as possible and spending as much time up there as i can.
4. Once I bring everything home I wash the material to get rid of the small particulates and any organic material. Then I let the material dry.
5. Once the material is dry I use 3 sieves to rid the material of sizes smaller than .180 mm and larger than .425 mm. Most micrometeorites fall in the range of .2-.4mm so that is the size you want to look for. Although some have been found at .7mm and even .07mm.
6. Now that I have everything clean and the right size I take another magnet and hover it over the material to collect all magnetic material including the possible micrometeorites. I transfer this material over to a microscope slide and I look at it under my microscope using a sweeping motions combing every inch of material and looking at every grain of dirt. I'm looking for roundish, and blackish spheres. They don't have to be perfectly round, most aren't, and they don't have to be black, but this is a good technique to start until you can pick them out right away.
7. Once I have identified the possible micrometeorites I will either place them on a micro-fossil slide with a white post-it note paper upside down to store the them or I will transfer them to a SEM sample holder with black carbon tape. I will usually try and take some images myself of them (the full process is listed above under the "more info" tab) and then I bring the MMs to the University of Minnesota for analysis and imaging.
8. Lately I have been cleaning the micrometeorites in a jewelry ultrasonic cleaner, this gets them extremely clean, all of the little particles come off in the vibrating water I submerge them in. They are contained in a microscope objective case filled with purified water.
9. The last and current step is to gather as much data as possible and try and contribute to science with any interesting findings that you have.
You don't need a fancy microscope or expensive sieves to find micrometeorites. All you really need is a decent microscope and a magnet, that with the right location and you can also find micrometeorites when you know what to look for. Kitchen sieves work just was well and Ebay might be a good place to look for used equipment.
Jon is a musician, a record producer, an author, a mentor and a pioneer. He is the first person in the world to find micrometeorites in urban areas, Jon has taught me what to look for and what to discard, and knowing what to discard is very important when searching for micrometeorites, it was perhaps my biggest blunder when getting started. Jon has also helped me with imaging (including the wonderful colored images shown on this site). His knowledge of micrometeorites is astounding and he has helped me with almost everything I know about micrometeorites today. Without his help I would still be looking at human made spheres claiming to have particles from space. I'm not sure where he finds the time but he even answers most of my 10,000 daily questions, a great mentor indeed.
You can find more about his project here...
And his book here...
Martin finished his PhD studying planetary sciences at Imperial College London and The Natural History Museum, London. He is extremely knowledgeable with micrometeorites as a whole and is currently focused on mostly unmelted micrometeorites. He has been willing to help me with any questions I have had and he also provided the unmelted micrometeorite image. Here are just a few examples of his excellent work...
Dr. Ginneken is a cosmochemist that specializes in micrometeorites and impact spherules. He as collected micrometeorites from Antartica and even on the rooftops of cathedrals in the UK. He has more scientific papers than I am able to count and has even helped with my first true scientific paper. Here are a few articles about his most recent work.