| The Sun, our star, gives light and heat by its electromagnetic
radiations, making life on Earth possible. It also emits
another type of continuous radiation, called the "solar
wind" (video 1 & 2, picture
1), This one consists of charged
particles not without danger for the Earth and its
environment. The study of the solar wind is very important.
As it crosses interplanetary space, it is useful to
know its major characteristics, especially when one
wants to travel through it with spacecrafts. Moreover,
the solar wind is a determining factor for the environment
closer to the Earth in space. Fortunately, the Earth
has a magnetic
field that protects us by deviating the majority
of charged particles of the solar wind.
Moreover, during solar activity at its highest (picture
2), strong solar eruptions are produced, often
coupled with coronal
mass ejections (gigantic bubbles of ionised gases,
emitted by the solar
corona), (video 3) and
an increase of the solar wind. The effects of such phenomena
include disruptions in telecommunications, damage in
the electronics of artificial satellites and aircrafts
flying at high altitude, disturbances in electric networks,
and even saturation of satellite detectors observing
the Sun (video 4). The well-being
of astronauts is also in danger, either by long-term
exposure to ionised radiations, even if these radiations
are of relatively low level (cumulative effect), or
by single exposure to very high level of radiations.
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