The Sun attractlet or open · read card by card

The Sun

Convection shaped by magnetic field at the surface of a star, and hot plasma in the loops above it.

The Sun’s visible surface is convection shaped by magnetic field. Heat from the interior drives cells about 1,000 km across, the granules. The cells sweep magnetic field into the dark lanes between them, and where field gathers strongly enough it shuts convection down. Less heat gets through there, which is why sunspots are dark. Behind all of it, a dynamo inside the Sun rebuilds the field on a cycle of about eleven years. Above the surface, the field arches into loops that hold plasma at a million degrees and more, and some of those loops never settle. Twisted field lets go in flares of every size. The cards below use the same test as the Weather page: does a structure’s own activity release the energy that drives it, or only carry energy delivered to it?

How to read a card

Each card is one solar structure. Its small tag is an authored reading of the real structure, a teaching device, not a measurement. The kernel says nothing about the Sun.

Red, natural attractlet · § 7.4: “a naturally-occurring non-recursive structure that exhibits attractor-like behavior under external driving.” Gold, reading open: the test does not settle it, and the card says why.

Neither tag reads the simulation. Any program that runs these structures is an attractlet model under § 7.4, as on the Lorenz page.

Granules and Magnetic Field

natural attractlet · § 7.4

Convection cells that sweep a magnetic field into the lanes between them, and a field strong enough to shut the cells down: the physics behind the dark lanes, pores and sunspots. Runnable now.

BasinHeated, magnetized layers that settle into cells with the field gathered between them. Strong enough field shuts the cells off, and the still, magnetized layer takes the basin.

Enter simulation →

The Sunspot Cycle

reading open

The dynamo that rebuilds the Sun’s field about every eleven years and marches bands of field toward the equator. Each part of the field is converted into the other by flows the field does not make, which is why regeneration alone does not settle the reading. Runnable now.

BasinRotating, convecting stars whose dynamo is strong enough to sustain a cycling field. Below that threshold any seed field decays away.

Enter simulation →

Coronal Loop Cycles

reading open

A loop of hot plasma, heated near its feet, that fills, overcools, rains back down and refills, hour after hour. The closed curve is in its temperature and density, not in the shape of the arch. Runnable now.

BasinLoops heated mostly near their feet, where no steady state exists. Spread the heating along the loop and it settles into a steady glow instead.

Enter simulation →

Flares as Avalanches

reading open

Stir a magnetic field slowly and it lets go in jumps: flares of every size, with no typical size, from one threshold rule. The model that made that argument, running live. Runnable now.

BasinStirred fields that settle at their own breaking point, whatever state they start from. Stop the stirring and the pattern freezes where it stands.

Enter simulation →

Closer to home: Weather →, and the plain Convection Cells → these granules grow from.

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