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enjoy the programs. Hello the solar wind is matter, blown from the sun out into

the whole solar system at up to 2 million miles per hour. We notice its impact

when Earth's magnetic field diverts it towards our poles from the northern and

southern lights or when it makes comet tails or when it damages electrical equipment. It was Eugene Parker in it was and ever since we've been sending out probes to learn more about this phenomenon

so fundamental to understanding life and the universe.

We'd me to discuss solar wind, Helen Mason OBE, reader in solar physics at the

Department of Applied Mathematics and Theoretical Physics, University of Cambridge,

Fellow at St Edmonds College, Tim Hawbury, Professor of Physics at Imperial College London,

and Andrew Coates, Professor of Physics and Deputy Director in charge of the solar system at Mulard Space Science Laboratory University

College London.

Andrew Coates, I've summarised that very elliptically.

Can you tell us more about what the solar wind is?

Well the solar wind is a stream of material coming out of the sun all the time.

It's about a million tons per second.

It's gusting, it changes with time, but it also comes out of speed which is between 1 and 2 million miles per hour.

Those numbers are very big, but what we can say is how far it's going in a second

so actually the 1 million miles per hour is equivalent to about 300 miles per second

so you know imagine something about 300 miles per second it gives you an idea of

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