How to collect micrometeorites in your own backyard this August
Don Deever, Assistant Professor, Extension Educator
University of Nevada, Reno Extension
“Catch a Falling Star” was one of Perry Como’s greatest hits, but the idea behind the song is more than just a fantasy. Few people know that they can actually catch micrometeorites from meteor showers in their own backyard. It’s a simple, yet exciting, science project a child of any age can enjoy. I’ll be sharing this project with our 4-H youth here in Nevada, for whom Extension is continuing to provide at-home and online STEM programs, amid the COVID-19 pandemic. But, it’s an interesting and uplifting activity we can all enjoy, reminding us there’s still a whole Universe out there, and to “reach for the stars.”
Timing is everything
Every year, there are nine meteor showers that are rated as “Class 1” events, which means they are the meteor showers that are most exciting to see, which also produce particles that fall from the sky that anyone can catch. In general, any Class 1-designated meteor shower means that you should be able to see at least 10 meteors per hour (depending on the darkness and clarity of the night sky) at the shower’s peak.
One aspect that frequently affects these dazzling celestial displays is the moon phase. The fuller the moon, the less meteors can be seen against the brighter background. But, even if it is difficult to see the meteors in the night sky, the particles can still be caught to be viewed, up close and personal, if you know the predicted date of the event for that year.
Every summer brings the Perseid meteor shower, which is generally considered to be the finest meteor shower of the year, renowned for displaying up to 100 “shooting stars” per hour. This year, it is predicted to peak Aug. 11-13, so mark your calendars now and gather a few simple supplies to prepare.
For three days and three nights…
The simple way to catch, observe, and suddenly come into possession of a piece of a shooting star is to set out a plastic wash basin, partially filled with enough water to cover the bottom by about a half-inch, and leave it outside for three days and nights. The basin needs to be in an open, exposed area, so no roof or tree foliage interferes with the collecting of the micrometeorites.
It should also be placed where creatures are not likely to drink from it, just to prevent thirsty critters from inadvertently slurping up one’s cosmic catch. There’s no exact amount of water that is required, but make sure the basin is full enough so that it doesn’t completely dry up from evaporation, and not too full to pose any hazards of drowning or otherwise.
Set the basin out the day before the meteor shower is supposed to peak, leave it there the day it peaks, and the day after, for a total of 72 hours. This year, this is predicted to be Aug. 11-13. On the morning of the fourth day (Aug. 14), it is time to harvest the micrometeorites.
Plastic cup + magnet + paper plate = star dust
The streaks of meteors that one sees, as they enter Earth’s atmosphere, result when the outer layer of the tiny meteoroid glows with the heat of friction. Fortunately, many of them don’t burn up completely. Instead, after they enter the lower reaches of the atmosphere and cool off, they settle down out of the sky as metallic dust, usually made of nickel and iron. Both have magnetic properties, which means that they are attracted to a magnet.
So, when it’s time to harvest your star dust, place a magnet inside a small plastic or paper cup, then slowly swish the bottom of the cup around through the dark materials in the bottom of the basin. Some of the “dirt” on the bottom of the basin will be pollen, dirt or other pollutants from the air. But, since the micrometeorites are composed of nickel and iron, they will immediately stick to the bottom of the cup, while the other debris will not.
At this point, pull the cup with clinging micrometeorites out of the basin, let the water drip off, then aim the cup over the center of a paper plate. Pull the magnet out of the inside of the cup, and the micrometeorites stuck to the bottom of the cup will instantly drop off into the plate that is waiting to catch them.
If one were to just stick the magnet in the water to attract the micrometeorites, it would be almost impossible to get them off the magnet afterwards. This method was thus designed to make sure that the magnet and the micrometeorites never touch. This is also the reason for using a plastic wash basin for the collection of the particles. If the basin was made of metal, for example, it could be difficult to remove them from the water.
Want a closer look?
Looking at the result of one’s micrometeorite collection on a paper plate can be anticlimactic at first, since they only appear to be a collection of tiny flecks of black dust. However, using a microscope, those little particles of dust can look like giant asteroids with pits and holes, and a burnt fusion crust, similar to what one sees in the movies.
In fact, if you want to go all out, some excellent USB computer microscopes can be purchased online for reasonable prices (less than $30). These little illuminated microscopes plug directly into the USB port of computers to magnify and project the object being viewed onto one’s computer screen.
Can’t “catch the stars” this August? No worries.
There are actually four more meteor showers that come after the Perseids this year. Here they are, with their predicted peak dates:
The Orionids, the second-most popular nighttime show among star gazers, Oct, 22.
The Leonids, Nov. 18.
The Geminids, Dec. 14.
The Ursids, Dec. 21, the first day of winter.
So, “catch a falling star.” Gazing upon these extraterrestrial visitors brings lasting memories to adults and children alike, and connects Earth-bound mortals to the wonders of infinite space from our own backyards