#micrometeorites

Every second, billions of teeny-tiny missiles strike Earth. They come from outer space. But it’s not an alien attack. These speeding objects are actually bits of space dust. They come in all sizes. Some contain only a few molecules. Others are similar in size to the specks under your bed that glom together into dust bunnies. And the biggies? They can be the size of sand grains.

Some of these specks formed when asteroids slammed into planets, moons or other space rocks. Others are debris left behind by comets streaking around the sun. And a few have traveled in from way outside our solar system. What all of these motes have in common is speed. They fly at up to 72 kilometers per second (45 miles per second). That’s 50 times faster than a speeding bullet!

Such super-speedy dust grains can damage equipment orbiting in space. In fact, they can punch right through metal or glass. So why don’t these falling microrocks harm our roofs or roads — or even our bodies? Thank a gigantic shield that protects our planet. The air all around us may seem like nothing. To a dust grain zooming through the near-emptiness of space, however, that air might as well be a solid wall.

After smacking into the atmosphere, space dust slows down. Some bits vaporize, giving off a lot of heat and light. Specks the size of a grain of sand or larger can shine brightly enough to see. These are known as meteors, or shooting stars. (Larger space rocks can become shooting stars, too.) Some space dust vaporizes completely. But other specks melt, solidify again and then fall gently to the ground. There, they tend to mingle with all of the other dust from various sources.

This jazz musician gives advice on how to search for stardust that might be covering your roof.

The cosmos is a swirling soup of stardust. Every day, approximately 60 tons of dust from asteroids, comets, and other celestial bodies fall to the Earth. These tiny metallic, alien stones of various shapes, textures, and colors—known as micrometeorites—are some of the oldest pieces of matter in the solar system.

Even though micrometeorites blanket the Earth, scientists have generally only been able to discover them in remote places devoid of human presence, such as Antarctic ice, desolate deserts, and deep-sea sediments. Scientists began searching for micrometeorites in the 1960s, and they predominantly thought the extraterrestrial dust would be impossible to find in urban environments. The conventional wisdom held that densely populated areas had too much man-made sediment that camouflaged the tiny space particles.

But Jon Larsen, a Norwegian jazz musician and creator of Project Stardust, was able to show that it is possible to find micrometeorites in more populated areas. In a study published in January 2017 in the journal Geology, he and his colleagues catalogued more than 500 lustrous micrometeorites (and counting), all recovered from rooftops in urban areas.

Larsen has some tips for intrepid stardust hunters. “The easiest way to find a micrometeorite is to start with the right roof,” Larsen says. Learn more and view micrometeorites from Larsen’s collection here.

Micrometeorites

Every second, billions of teeny-tiny missiles strike Earth. They come from outer space. But it’s not an alien attack. These speeding objects are actually bits of space dust. They come in all sizes. Some contain only a few molecules. Others are similar in size to the specks under your bed that glom together into dust bunnies. And the biggies? They can be the size of sand grains.

Some of these specks formed when asteroids slammed into planets, moons or other space rocks. Others are debris left behind by comets streaking around the sun. And a few have traveled in from way outside our solar system. What all of these motes have in common is speed. They fly at up to 72 kilometers per second (45 miles per second). That’s 50 times faster than a speeding bullet!

Such super-speedy dust grains can damage equipment orbiting in space. In fact, they can punch right through metal or glass. So why don’t these falling microrocks harm our roofs or roads — or even our bodies? Thank a gigantic shield that protects our planet. The air all around us may seem like nothing. To a dust grain zooming through the near-emptiness of space, however, that air might as well be a solid wall.

After smacking into the atmosphere, space dust slows down. Some bits vaporize, giving off a lot of heat and light. Specks the size of a grain of sand or larger can shine brightly enough to see. These are known as meteors, or shooting stars. (Larger space rocks can become shooting stars, too.) Some space dust vaporizes completely. But other specks melt, solidify again and then fall gently to the ground. There, they tend to mingle with all of the other dust from various sources.

The Scientific Research Notes of S. Sunkavally (years:2002-2011).

To commemorate the International Day of Light convened by UNESCO annually, NASE proposes to all its participants and instructors to carry out a simple experience but of great educational interest. Although the day of light is May 16, it is proposed to all participants to do it throughout the half year, from the March equinox to the September equinox. It is not limited to May 16 because, as is well known, this day falls within the rainy season in some countries. For this reason, interested teachers can be carried out with their students for half a year. We request that you send us some testimonial photos and the data in the observations obtained during the development of the experience. The table in the introductory material to read to prepare for the experience. Good luck and have a cloudless day or night to do so.

This is a NASE’s proposal for the International Day of Light and consists in Introducing Astrobiology in Schools by means of an activity based in looking for micrometeorites any day between March 20 and September 23, 2023. NASE, Network for Astronomy School Education. Light, Cameras and Life.