By Max Liboiron.

One of the central tensions in discard studies is the othering and externalizing of  waste that originates in often intimate and everyday spaces and processes. This tension is maintained via material infrastructure (see, for example, Jennifer Clapp’s “The Distancing of Waste” or Coverly’s “Hidden Mountain“) and social), taboo (see Douglas’ Purity and Danger, or Inglis’ Dirt and Denigration), or other social and material systems. Yet it is always prone to disruption, where the outside comes inside, the other becomes familiar, the far away comes into the home or body, and the taboo becomes sacred. An exotic but perhaps quintessential case is space dust.

Ryan Thomspon’s short but sweet article, “The Dark Flight of Micrometeorites,” in Making the Geologic Now, illustrates the mundane commonality of tiny debris from outer space. Xenogarbology, or the study of space trash, becomes an intimate, at-home discipline in the face of micrometeorites. It’s a nice counterpart to the many stories and anxieties over earth-defeating meteorites since the appearance of one over Russia last month.

These ‘turtlebacks’, photographed by Jon Larsen of Project Stardust, are part of an ongoing study using typologies to differentiate micrometeorites from microscopic terrestrial spherules. Image courtesy: Jon Larsen, 2011.

Every day some 200 tons of extraterrestrial material enter the Earth’s porous atmosphere….The smallest of these materials, however, make it to the surface of the Earth as micrometeorites without much in the way of fanfare. No fiery explosions in the sky. No damage or destruction. Just a silent fall to Earth.

By definition, these micrometeorites are generally less than 1mm in diameter—literally dust-sized. However, what they lack in theatrics or destructive power, they make up for in numbers. While a meteorite impact that has the ability to cause regional destruction may occur once every 10,000 to 100,000 years, micrometeorite “impacts” occur millions of times daily. Estimates vary widely with respect to just how much of this material the earth collects, with some studies claiming that the annual influx weight of these objects may be upwards of 14,000,000 tons. Far more likely, however, are estimates in the 10,000 to 20,000 ton range. On the low end of these estimates, the daily influx works out to some 27 tons per day, accounting for the majority of extraterrestrial materials on Earth.

An unclassified metallic spherule (possible micrometeorite) on the tip of my index finger. Image Courtesy: Ryan Thompson, 2012

Yet it is not sheer quantity and an even distribution that makes space dust less alien and more everyday. The fact is, we regularly make meteorite look-alikes with similar compositions so that it is difficult or even impossible to distinguish our micro debris from micrometerorites.

For the past few decades the lay community believed that searching for micrometeorites was as simple as collecting rainwater or sweeping up road dust and examining it under a microscope. While true that this approach may yield micrometeorite specimens, the authentication of these small metallic spherules as such is much more complicated. As it turns out, there are certain post-industrial processes, the flicking of a lighter or the use of a grinding wheel, among others, that have the ability to create morphologically similar objects.
In fact, in any successful rainwater or road dust sample one will also find scores of false positives, or “micrometeorwrongs.” If with every flick of a lighter, we create a handful of micrometeorwrongs, it’s not difficult to imagine these newly formed spherules existing alongside their micrometeorite counterparts for hundreds of years, or perhaps thousands, into the future. Scientists have therefore turned to collecting micrometeorites from pre-industrial melted arctic ice, and from the tops of mountains. To the layperson, however, it may all be the same. Micrometeorite or micrometeorwrong, we can imagine these dust-sized particles landing on Earth after being polished round from their multi-billion year journeys through space, ready for our rain-collectors, magnets, and microscopes, and ready for us to re-imagine our relationship to the cosmos as messier and more complex than we ever imagined it.

Thus, we have to go to our own earthly frontiers, areas less-touched by humans, in order to find very common space dust. Micrometeorites are now too-everywhere, too mixed in with everyday micrometeorwrongs, for accurate extraction and study. The far away and everywhere categories flip flop again.

Finally, Thomspon finishes with a temporal categorization of the everyday versus micrometeorites that makes them strangers once again, showing that space dust is a great material for un/re/classifying the inside/outside, other/familiar, exceptional/everyday categories of discards:

Despite floating through space for millions of years, upon arrival on Earth, micrometeorites become as much a part of our everyday, as they are a part of the origins of our solar system more than 4.6bn years ago. To compare our day-to-day human time scales to the time scale of micrometeorites in this fashion feels both humorous and humbling. That we might understand during an average lifetime what constitutes the space of billions of years, let alone thousands, seems quite impossible. But it’s worth trying because doing so adds new perspective to our perceptions of time.

Max Liboiron is a postdoctoral researcher with the Intel Science and Technology Center for Social Computing and the Superstorm Research Lab.