Kevin Fong demonstrates how hard it is for a spacecraft to catch up with the International Space Station.
This is because the speed of an orbiting object is related to the height of its orbit, so when the spacecraft is closer to the Earth than the ISS, it is travelling faster, so in theory it could catch up with it.
However, as it rises higher from the Earth and closer to the orbit of the ISS, it slows down, and potentially falls behind the ISS.
A student from the audience demonstrates the technique used, using a model demonstration on the floor of the lecture theatre.
This clip is from the Royal Institution Christmas Lectures 2015.
Teacher Notes
Students could be introduced to the equations that explain circular motion, and how these can be used to explain the link that Kevin describes in the clip between altitude and speed.
Curriculum Notes
This clip will be relevant for teaching KS3 and GCSE Physics.
This topic appears in OCR, Edexcel, AQA, WJEC KS4/GCSE in England and Wales, CCEA GCSE in Northern Ireland and SQA National 4/5 in Scotland, and Cambridge IGCSE Physics.
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Dr Kevin Fong and NASA astronaut Dan Tani explain the danger of space debris.
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Dr Kevin Fong shows how a Geiger-Muller tube can detect ionising radiation but not the type of radiation, and how detectors on the International Space Station can.
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Why tardigrades can survive in orbit. video
Dr Kevin Fong explains why tardigrades are so resilient when exposed to ionising radiation lethal to most other organisms.
How to recycle urine in space. video
Dr Kevin Fong demonstrates a urine recycling system that works using osmosis, concluding by drinking the liquid that is produced.
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