Interactive · Resolution, web edition
Watch a molecule get weighed.
Resolution is my newsletter for making one complicated thing clear. This is its web edition. Below is a working model of a mass spectrometer, the machine that weighs molecules far too small to see. Drag the weight and watch what happens.
Weight set to 42 units. A molecule this light curves hard in the field and lands high on the detector. Drag the slider to compare.
That is the whole machine. It cannot put a molecule on a scale, so it does something cleverer: it turns weight into a position you can read. Here is the same idea in words.
Move one
Give it a charge
The machine knocks an electron off each molecule, leaving a tiny positive charge. A charged particle can be pushed by electric and magnetic fields. A neutral one cannot. Charge is the handle.
Move two
Bend its path
The charged molecules are sped up and sent through a magnetic field, which curves their flight. The field bends a light molecule more than a heavy one, the way a gust pushes a ping-pong ball further off course than a golf ball. Weight has become an angle.
Move three
Count where it lands
A detector counts how many molecules arrive at each angle. A sharp curve means light. A gentle curve means heavy. The pattern of landings tells you exactly what the sample was made of, one molecule at a time.
The same issue, two ways
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This started as Resolution Issue 01, a real HTML email. Read the email edition, then see the standard operating procedure that documents how it was hand-built to survive Outlook.
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The same instinct, turned on real audiences instead of a model, is under Work.