Electron Microscope Mystery 6

It’s funny how when I posted Mystery 5 I thought that after August, things would calm down (at NSF and in life). Ha! No.

So I bring you another microscope mystery! The photo below is about half a millimeter across. What do you think it is?

Update: 1:10p

This is proving to be a tricky one, so here’s a 5mm-wide view…

Update: 1:18p

Nice job in the comments, Lori! The first image is a soldered portion of a ring – an engagement ring, in fact. A few years ago, my intern got engaged. She came into the lab and asked me to check if the diamond was real. I asked, “are you sure you want to know the answer?” She did. It was.


Electron Microscope Mystery 5

July and August are incredibly hectic months for my programs at NSF, so I have been a major slacker here at FS. To make up for it, I bring you a new electron microscope mystery! The field of view here is 6mm. What do you think it is?

Update, Wednesday August 8, 8:40a: This seems to be a difficult one! So here’s a second image, same scale, of the other end of this object. A hint: Many of us depend on a bunch of these, daily!

Update, Saturday August 11, 4:40p: Well, this proved difficult for everyone I spoke to, on and off this page. Here’s the answer: It’s a link in a bike chain!


Electron Microscope Mystery 4

We’re back with another electron microscope mystery… Can you guess what this is? The image is 1 mm wide.

Update, 1:53p: Karon guessed ‘speakers,’ which is pretty close! It’s the metal mesh on one of my iPhone earbuds:


Electron Microscope Mystery 3

It’s time for the Third in my series of electron microscope mysteries (click to see One and Two).

The width viewed in the top image is ~ 100 microns (0.1 mm) and the bottom ~700 microns (0.7 mm). Can you guess what it is?

Note: Some of my DC friends have seen this before, so I ask them to kindly let others guess.

Update, 5:05p: Nice job, Callan! Staples on end is right:


Electron Microscope (non-)Mystery 2

I have been swamped, both in the office and in life, but I wanted to share another favorite electron microscope image. This is a crack in a rough, scratched, metal surface:

Which to my eyes looks very much like a river gorge and delta, with all the water stripped away (like, say, the Nile):

But really, it’s just a worn out soldering line in a long-worn, much-loved silver ring.


Electron Microscope Mystery 1

Before I became a federal funder, I ran a beautiful environmental scanning electron microscope (E-SEM). Unlike the binocular microscope you probably peered into as a student, an SEM uses electrons, not light, to produce an image. Because electrons are so tiny, you can see things at a much higher magnification than you can with light.

Other reasons electron microscopes are cool include 1) things closer to the beam appear lighter, and things further, darker (as though they’re in ‘shadow’) giving the appearance of 3-dimensionality, and 2) materials made of heavier elements have a higher contrast (and appear brighter) than materials made of lighter elements (which appear darker). For example, if you looked at an object made of aluminum (Al) and lead (Pb) stripes, the Pb lines would be brighter than the Al stripes.

For decades, electron microscopy required that samples be very small, polished flat, and coated in something conductive, like gold or carbon. An ‘environmental’ SEM, however, has a huge chamber, within which you can put a range of materials of varying shapes:

Left photo from John Pinizzotto: http://wildcatphysics.blogspot.com/ .... Right photo from/of me.

When I met my first E-SEM over 4 years ago, I needed to see what materials and shapes fit in the chamber, and which responded well enough to the beam to get good images. So like any good scientist, I experimented. These experiments resulted in a collection of electron microscope images of everyday objects, and I quickly realized the joy that comes with making friends guess what the objects were, based on high-magnification electron images. I ran this series on Flickr for a while, years back, but thought I would resume the fun here.

Thus, I give you #1 in the Electron Microscope Mystery series. The image below is about 70 microns across (0.007 cm). Can anyone guess what this is? I’ll update later in the day with a wider field of view.

Update at 1:20p: Added two views, each zoomed out a bit more (the width of the last is about 0.7mm wide…

Update at 2:40p: It’s been solved! These are ink particles pressed into paper fibers. The sort of pointed shape you see is the point of an upside-down letter M: