The Spacetime Metric

Ages 8–12 · about 6 minutes

Glowing Balls That Hold Themselves Together

Can a glowing ball of hot gas really hold its own shape?

The big idea

Hot gas can wind itself into a knot and hold its own shape.

plasma
A gas so hot that its pieces come apart and carry electricity.
plasmoid
A blob of plasma held together by the magnetism it makes itself.
provenance
Where a photo or video came from, and who can prove it.

Can a glowing ball of hot gas really hold its own shape?

For centuries people described ball lightning. A glowing sphere drifts through a room during a storm. It hangs in the air, then quietly vanishes. Scientists mostly did not believe them.

Then in 2014 a team of Chinese researchers got extraordinarily lucky. They were pointing their instruments at a thunderstorm when a ball of lightning appeared. They caught its light and read the colors in it.

A copper coil standing in dark water with glowing rings of current circling around it, while the water inside stays perfectly still.
Glowing rings circling round and round in dark water. Real plasmoids make rings too, out of hot gas and magnetism, and they hold their shape without any container.

What we know for sure

Heat a gas far enough and something new happens. The atoms come apart into pieces that carry electricity. That is plasma, and it is what stars and lightning are made of.

Now the clever part. Moving electricity always makes magnetism. And magnetism squeezes anything electric that moves through it. So a plasma can build a magnetic field that squeezes the plasma itself.

That loop lets a blob of plasma hold together with nothing around it. Winston Bostick gave these blobs a name in 1956. He called them plasmoids. Laboratories now make them on purpose, every single day.

The ball lightning colors told a lovely story too. They matched elements found in soil. The ball was made from the ground it had struck.

That is the sort of clue scientists love. It does not just say the ball was real. It says where the ball came from.

What scientists are testing right now

Here the ladder gets interesting. An inventor named Ken Shoulders spent forty years on something stranger still. He reported tiny specks holding hundreds of billions of electrons at once.

There is a real puzzle in that. Electrons shove each other apart ferociously. Squeeze that many together and they should fly apart instantly.

Shoulders said his specks bored clean cold channels straight through ceramic. In 2022 a former Naval Research Laboratory physicist named Graham Hubler published a possible explanation. Scientists are testing this idea. No modern laboratory has repeated the measurement yet.

There are also videos of glowing orbs flying near an aircraft. Careful people have studied them and reached different conclusions. Some read them as real objects. Others rebuilt the scene on a computer and got something similar. What is missing is provenance, meaning the original camera files. The people studying it said in advance what would settle it, which is exactly right.

Why it matters

Plasmoids are not a curiosity. Some fusion machines work by squeezing one on every single shot. You will meet those in a later lesson.

Understanding how anything organizes itself is one of the deepest tricks in nature. Storms do it. Galaxies do it. So do you.

Your turn

What else in the world holds its own shape with nothing holding it? Think about smoke rings, whirlpools and hurricanes.

Nobody has fully explained ball lightning yet, after hundreds of years. Perhaps you will.

Try this at home

The invisible ring cannon

You need: A plastic cup, a balloon, sticky tape, tissue paper, and a grown-up with scissors

  1. 1.Ask a grown-up to cut a hole the size of a coin in the base of the cup.
  2. 2.Cut the neck off the balloon, stretch the rest over the open top, and tape it down.
  3. 3.Hang a strip of tissue paper across the room. Aim the hole, pull the balloon back and let go.

Notice: The tissue flutters, though you saw nothing cross the room. The air left as a spinning ring that holds its own shape the whole way. Nothing holds it together except its own motion. Plasmoids do the same trick using magnetism.

For grown-ups and older readers

This lesson comes from Chapter 9: Exotic Vacuum Objects, Plasmoids, and the Orbs and the map unit Plasmoids, charge clusters and the orbs.