FREE SHIPPING ON ALL FINE ART ORDERS

FREE SHIPPING  ON ALL FINE ART ORDERS

NOW SHIPPING TO EU, USA, CAN, NOR, NZL, AUS, CHE

NOW SHIPPING TO EU, USA, CAN, NOR, NZL, AUS, CHE

SHIPPING TO UKCOMING SOON

SHIPPING TO UK COMING SOON

ABOUT          EVENTS          BLOG

PROJECT STARDUST

SHOP FINE ART

FULL MENU

Micrometeorites

An Introduction to Micrometeorite Types: Scoriaceous

Shortly after I discovered the world’s first urban micrometeorite in 2015, I began engaging with fellow micrometeorite enthusiasts from around the world on social media. Every week I receive fascinating questions about these enigmatic particles. Some time ago, I decided to write a blog post series to summarize the various types of micrometeorites as they were classified in a seminal paper by Drs. Matthew Genge, Cecil Engrand, and Susan Taylor.

When cosmic dust particles end their journey, their path through our atmosphere most often transforms the rough, unmelted micrometeoroids into polished jewels. However, in the case of scoriaceous micrometeorites, which I discuss in this article, the particles remain in a mainly unmelted state due to variations in the angle of entry and initial mass and speed. As one might imagine, this leads to substantial differentiation in both chemical and morphological characteristics.

Jan Braly Kihle and I recently began a new research project with Dr. Roar Skartlien from the Institute for Energy Technology (IFE) in order to learn more about how micrometeorites are formed. Our hope is deepen the classification work that Genge et al. (2010) spearheaded.

Today I present a summary of scoriaceous (SC-type) micrometeorites; I hope you find it both fascinating and helpful. Enjoy!

Scoriaceous (SC-type) Micrometeorites

For reasons not fully understood, some micrometeorites survive atmospheric entry as unmelted, or low heated particles. Whatever the mechanism, the peak temperature of these enigmatic particles does not exceed 1,350°C (2,500°F). During this low heating, volatile elements expand and escape as gas bubbles resulting in a vesicular or scoriaceous micrometeorite.

Under a microscope, Sc-type extraterrestrial particles (ScMMs) are dominated by micron-sized equant olivine crystals erratically suspended in abundant glass. Occasionally, you will also see magnetite crystals scattered on the surface.

These micrometeorites are sometimes hard to identify, due to their lack of aerodynamic properties and characteristic textures. But, with experience and a strong understanding of Sc-type visual morphology, it is possible to find them in urban dust samples using a simple light microscope. However, the best way to confirm a ScMM is with an electron microscope, since it is easy to verify their extraterrestrial origin due to their classic chondritic chemistry.

The collage featured at the top of this blog post shows twelve of these fascinating scoriaceous objects, all in the size range of 0.2 to 0.7 mm, all of which were found on rooftops of industrial buildings. Among >4,000 micrometeorites, these are almost all I have found of this type, so they are quite rare. One important question that comes to my mind is whether this rarity is a true reflection of their distribution among other micrometeorite types or caused simply by the fact that they are difficult to recognize?

These barely rounded particles are mostly transitions between porphyritic and scoriaceous, sometimes closer to the one and sometimes closer to the other. From the Atlas of Micrometeorites, we know that exact classification of ScMMs is only possible on sectioned particles, because the inner foam-like structure is what defines a micrometeorite as scoriaceous. The presence of large openings visible from the outside is not a real criterion for scoriaceous micrometeorites and is often observed on porphyritic olivine (PO-type) micrometeorites too. On the outside, we usually see a magnetite rim composed of octahedral magnetite crystals. This rim may vary in quality, and sometimes it is barely visible, partially visible, or not present at all.

Here are some scanning electron microscope (SEM) images that illustrate some classic ScMM features.

A detail SEM image of scoriaceous micrometeorite NMM 2595 by Project Stardust Founder Jon Larsen and Siri Simonsen
Detail SEM image of NMM 2595 by Project Stardust Founder Jon Larsen and Siri Simonsen at the University of Oslo. © Project Stardust, 2023.

This is a detail SEM image of the surface of scoriaceous micrometeorite NMM 2595. In the collage this particle is in the bottom row, second to the left. This is a strange mix of olivine and magnetite chunks. Truthfully, I do not even dare to call them crystals, even though they most likely are crystalline. This is a pre-stage to the order we observe in more heated particles, where elemental differentiation is accumulating all the dense elements (iron, nickel, platinum, etc) into a metal core and the olivine has developed into well formed crystals.

A SEM image of scoriaceous micrometeorite NMM 1459 by Project Stardust Founder Jon Larsen and Siri Simonsen
SEM image of NMM 1459 by Project Stardust Founder Jon Larsen and Siri Simonsen at the University of Oslo. © Project Stardust, 2023.

The SEM image above shows micrometeorite NMM 1459, which is in the top row of the collage on the left. You can see that the degassing of volatile elements was not completed and the matrix has not undergone elemental differentiation.

A detail SEM image of scoriaceous micrometeorite NMM 1459 by Project Stardust Founder Jon Larsen and Siri Simonsen
Detail SEM image of NMM 1459 by Project Stardust Founder Jon Larsen and Siri Simonsen at the University of Oslo. © Project Stardust, 2023.

And, last, here is a detail SEM image of the surface of the NMM 1459. The white specks, which are composed of magnetite, are starting to develop into octahedral crystals but the nickel-iron and sulfide has not yet differentiated into a core.

I hope you enjoyed learning about scoriaceous micrometeorites! If you’re curious, the micrometeorites in the featured image of this blog post are outlined below:

  • Top row: NMM 1459, NMM 3328, NMM 2073, NMM 2484
  • Middle row: NMM 4016, NMM 2530, NMM 3451, NMM 1240
  • Bottom row: NMM 2086, NMM 2595, NMM 828, NMM 601

Before I sign off, I’d like to extend my sincere gratitude to Thilo Hasse, Martin Suttle and Matthew Genge for their extraordinary contributions to this field and sharing information about these strange space rocks so generously. The exploration of the micrometeorites continues.

And, to you, I say a heartfelt THANK YOU for being here and, as always, if you have questions, please connect with me on FacebookInstagram, or Twitter. For questions about specific micrometeorites in this post, please be sure to use the catalogue ID!

To finish, I will simply say: please remember that we are always surrounded by beauty, even if all we see is dust.

Yours truly,

Jon Larsen

Just in case you're new here!

Together we have amassed the world's most expansive collection of micrometeorites and we can't wait to share it with you.

Whether you're an expert in the field, an art collector with an appetite for treasures from space, or a budding stardust enthusiast, we hope you'll enjoy learning about our work.

Connect with us on social media to share the excitement of seeing new micrometeorites for the first time!

Jon Larsen & Jan Braly Kihle

We're so glad you're here!

AS SEEN IN

AS SEEN IN

Framed Prints

SHOP NOW

CANVASES

SHOP NOW

Panels

SHOP NOW

Bundles

COMING SOON

WINTER 2022 COLLECTION

Meet this season's micrometeorites

This season's collection features a variety of stunning micrometeorites. From mountainous cryptocrystalline turtlebacks and bewitching glass spherules to ultra rare giants. Available for a limited time only.

NMM 1448: V-TYPE

NMM 1448:  V-TYPE

Glass / Vitreous

Glass or vitreous type (V-type) micrometeorites each a temperature of up to 2000°C (3600°F) as they descend through the atmosphere..

These delicate, translucent spherules are difficult to find due to their lack of magnetism, since most of their metals evaporated during descent. 

NMM 1359:  CC-TYPE

Crypto-crystalline

Cryptocrystalline (CC-type) micrometeorites are composed of glassy particles with fine-grained crystallites that are too small to recognize as individual grains.

Many of these magnificent spherules feature metal beads and aerodynamic forms, while others have a "turtleback" shape with humps distributed evenly around the spherule.

NMM 1359:  CC-TYPE

NMM 500:  BO-TYPE

Barred Olivine

Barred olivine (BO-type) spherules are coarse-grained  micrometeorites made of the magnesium variety of the mineral olivine, forsterite, which is punctuated with small particles of magnetite.

The surface features striations that are formed when iron reacts with oxygen in the atmosphere. 

NMM 500:  BO-TYPE

NMM 1149:  PO-TYPE

Porphyritic Olivine

Porphyritic olivine (PO-type) micrometeorites are also made of forsterite, a type of olivine that is made of magnesium.

There are many morphological varieties of this type of micrometeorite; From evenly distributed small crystals, to crystals that increase in side, to extremely large or even possibly a single olivine crystal.

NMM 1149:  PO-TYPE

NMM 1271:  Sc-TYPE

Scoriaceous

When stardust does not reach a peak temperature of at least 1350°C (2500°F) during entry and deceleration, it barely melts. Volatile elements expand and escape in the form of gas bubbles, which results in a scoriaceous (SC-type) or vesicular micrometeorite.

Micrometeorites of this type are extremely difficult to find.

NMM 1271:  SC-TYPE

NMM 1271: G-, I-, CAT-typeS

Other Types

From G-types with dark silicate glass, I-types dominated by iron, and milky CAT spherules  enriched with calcium, aluminum, and titanium, to fossil, unmelted, and un-categorized micrometeorites.

There is no question that Jon Larsen and Jan Braly Kihle's contributions have had a dramatic effect on the field.

NMM 1271:  G-/I-/CAT-TYPES

Jon and Jan are
EXCEPTIONAL ARTISTS AND SCIENTISTS. 

Michael Zolensky

NASA JOhnson Space Center

SEM Collection

COMING SOON

Never forget: YOU ARE SURROUNDED BY STARDUST, inside and out.

Color Collection

SHOP NOW

FIREBALL: Visitors from Darker Worlds

SEE JOn & Jan IN

From directors Werner Herzog and Clive Oppenheimer, this remarkable journey across our planet and universe explores how meteorites, shooting stars, and deep impacts have awoken our wonder about other realms-and make us rethink our destinies.

Limited Edition

The Atlas

of Micrometeorites

Never before has it been possible to see stardust in such a large format with crisp details. The 500+ color images are made possible by a new photo technology developed for this project by the author and mineralogist Jan Braly Kihle. 

SHOP NOW

The Atlas of Micrometeorites provides an INVALUABLE RESOURCE
for stardust hunters around the world.

Matthew Genge

Imperial College, London

ORIGIN STORIES

Jon Larsen revolutionized the study of micrometeorites when he became the first person to discover a micrometeorite from an urban environment. Then a new form of art emerged when he and Jan Braly Kihle created the world's first high resolution photographs of micrometeorites in colour.

Learn about the singular moment that led to Jon's groundbreaking discovery
and the phone call that kickstarted a truly epic friendship.

Jon Larsen revolutionized the study of micrometeorites when he became the first person to discover a micrometeorite from an urban environment. Then a new form of art emerged when he and Jan Braly Kihle created the world's first high resolution photographs of micrometeorites in colour.

Learn about the singular moment that led to Jon's groundbreaking discovery and the phone call that kickstarted a truly epic friendship.

I HAVE TO KNOW

I'm ready. TEACH ME.

Micrometeorites

Jon Larsen and Jan Braly Kihle have amassed the world's most expansive collection of urban micrometeorites and they want you to follow in their footsteps.

WORLD-RENOWNED EXPERTS ON

Connect & LEARN

SHOP

CONTACT    |     ACCOUNT

Asset 3

HALLO and welcome!

We're Jon Larsen & Jan Braly Kihle

We are world renowned micrometeorite experts here to share our cosmic art and inspire the world to become star hunters.

STARDUST
is everywhere