How can I teach the solar nebula with a demonstration?

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Show how spinning causes flattening, using a spinning pizza dough video or a rotating bowl, then model dust clumping into planetesimals with a tray of particles.

The idea that the Solar System formed from a spinning, flattening disc of gas and dust can be demonstrated simply.

Spinning and flattening. Explain that the cloud collapsed under gravity and spun faster as it shrank, like a figure skater pulling in their arms. Spinning made it flatten into a disc. Demonstrations: - A video of a pizza maker spinning dough, which flattens into a disc. - A swivel chair: a pupil holding weights at arm's length spins faster when pulling them in, shown carefully by the teacher. - A bowl of water swirled with tea leaves or glitter, showing how particles collect and swirl.

Sun in the middle. Most material fell into the centre, forming the Sun.

Dust clumping. Show how small particles stick together. Rub a balloon to give it static charge and dip it in tiny polystyrene beads or pieces of tissue paper: they cling and form clumps. In the solar nebula, dust grains stuck together by weak forces, forming larger and larger aggregates.

Planetesimals and planets. Model planetesimals with small balls of clay. Pupils 'collide' them gently to build larger bodies, illustrating how planets grew.

Meteorite link. Chondrites are like leftover clumps that never grew into planets. Their chondrules and matrix preserve the ingredients of the disc.

Evidence from other stars. Show telescope images of discs around young stars, such as those taken by the ALMA telescope, which reveal rings and gaps that may mark forming planets.

These demonstrations help pupils visualise processes that happened billions of years ago.

How can I teach the solar nebula with a demonstration?

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