Physics KS3 / GCSE: Why are bones weaker in orbit?

Kevin Fong uses a model skeleton to explain to the audience that bones begin to waste away when they are not put under the normal everyday stress of walking, standing and taking part in sports.

This is a problem for astronauts. Using an enlarged model of the inside of a bone, Kevin explains that the honeycomb structure of a bone allows it to be strong yet light.

However, bone wastage when an astronaut is in the International Space Station weakens the structure as the mineral density decreases.

A child from the audience stands on the original and the weakened bone models and the weaker one collapses.

This clip is from the Royal Institution Christmas Lectures 2015.

Teacher Notes

Key Stage 3

Before watching the clip, ask students to suggest what bones are made from (collagen protein and hydroxyapatite mineral) and what they would look like using a powerful microscope.

After the clip, students can research the structure of bird bones.

Key Stage 4

After watching the clip, students could research the composite nature of bones (collagen protein and hydroxyapatite mineral).

It is possible to demonstrate the two main components by placing identical bones from a raw chicken leg into either an oven for an extended period (to remove the collagen) or into dilute acid for an extended period (to dissolve the hydroxyapatite).

Search online for instructions from the Royal Society of Chemistry."

Curriculum Notes

This clip will be relevant for teaching Physics.

This topic appears in KS3 and OCR, Edexcel, AQA, WJEC KS4/GCSE in England and Wales, CCEA GCSE in Northern Ireland and SQA National 4/5 in Scotland.

More from the Royal Institution Christmas Lectures 2015

What is Newton's Canon and Third Law?
video
Using Earth’s rotation to launch a rocket
video
How the vacuum of space effects the human body
video
Resonant Frequency
video
Orbital Rendezvous
video
What does gas weigh?
video
How micro-gravity disorientates us
video
The danger of orbital debris
video
Demonstrating heat shield material
video
Why Earth rock is found on the Moon
video
Demonstrating radiation detectors
video
How Earth protects us from radiation
video
Why tardigrades can survive in orbit
video
How to recycle urine in space
video