Our Sun plays a central role in daily life, by warming and lighting the world, and powering the growth of living plants. Since ancient times, mankind has been aware of its importance, although not always understanding how or why. Now in the space age, man-made satellites monitor and probe the environs of the Sun, observing subtler and sometimes damaging effects on Earth. These charged particles can change the behaviour of electronic components in an unpredictable manner. In the worst case scenario, a satellite could be lost because of damage to some vital component.
Aircraft are also increasingly vulnerable as more functions come under electronic control.
In addition to the charged particles and plasmas which cause damage to individual satellite components, variations in solar activity affect the conditions at orbital altitudes above 120 km. Increased solar activity causes the atmosphere to heat and expand. For satellites in low-earth orbit this atmospheric change can then exert an increased drag on the satellites causing them to slow down and change orbit. Space weather conditions can also be hazardous to humans in space. Astronauts are normally well protected by large shielding in space stations.