Influence of the Solar Wind on the Earth
As we have already discussed in the chapter on the
Earth,
the solar wind can have a large influence on our planet. This is particularly true in times of
the active Sun (near sunspot maximum) when the wind is strong and can
contain bursts corresponding to flares and coronal mass ejections from the Sun.
The solar wind has a significant influence on our
ionosphere,
the Earth's
magnetic field, on Earth's
auroras,
and on telecommunication systems (see the right panel).
Earth's Ionosphere and the Sun
The level of activity on the Sun can have a large influence on the Earth's
ionosphere, as illustrated in the adjacent image and in this
animation.
The level of solar activity has similar effects on related phenomena such as
Earth's auroras.
The "Space Weather" Report
One can monitor
solar data
for the last 30 days.
These data give information on
solar flares, sunspots, X-ray and radio-frequency fluxes.
One can even tune into
Today's Space
Weather, which gives a "weather report" of current and predicted
conditions in space with respect to the solar wind, solar activity, X-ray
activity, and related phenomena.
For example, here is the space weather outlook that was reported
on January 27, 1998:
In this report, the region numbers refer to active areas on the Sun, C and M
are classifications of solar flares, and CME stands for a coronal mass ejection.
As noted earlier in conjunction with the ill-fated Telstar 401 satellite, "space
weather" may have non-trivial practical consequences.