What is Space Weather?
The Sun Earth Connection: Huge eruptions from the sun, can send billions of tonnes of plasma towards the Earth.
The Sun does not only emit heat and light. Every second a million tonnes of hot plasma, electrons and ions, escape the Sun's gravity. This solar wind buffets any obstacles, including Earth's magnetic shield.
However, even this is leaky and
lets electrons and ions through to cause the aurora and problems for
satellites. Without solar wind, the Earth would be like a bar magnet in space.
With the solar wind, the magnetic field is compressed like a balloon on the Sun
side and dragged out into an invisible comet-like tail behind.
The Aurora: The visible sign that solar activity is affecting the Earth.
Conditions
depend on the 11-year solar activity cycle, the 27-day solar rotation and the
interplanetary conditions. Near solar maximum, as in 2000, there are more
coronal mass ejections from the Sun, tens of billions of tonnes at a time,
which disrupt the constant flow of the solar wind. Also there are more flares
which hurl faster particles Earthwards. Space weather is about all these
effects - and their influence on the Earth and mankind's technological systems.
At MSSL, we are conducting research into space weather effects.