What is Space Weather? It can make even the most
destructive tornado here on Earth look like a gentle breeze. Eruptions from
the Sun, the disturbances in the solar wind, and the twisting and stretching
of Earth's magnetic field: collectively, we call it space weather. And, just
like weather here on Earth, it can be both mild-and wild.
A view of the Aurora Australis -- the Southern Lights --
taken from the Space Shuttle Discovery in 1991. The tail of the
shuttle can be seen to the left.
Photo courtesy of NASA.|
Everyone is familiar with changes in the weather on Earth such as rain,
snow or a powerful hurricane. But faraway changes on the Sun and in
can cause another sort of weather that can effect
life on Earth: Space Weather.
There are four realms in our Sun-Earth Environment:
|A powerhouse of energy and the source of the solar wind roaring through space
||Full of charged particles and plasma spread by solar wind, marked by invisible magnetic fields.
|A giant magnetic field surrounds Earth, pushed out of shape by the powerful solar wind.
||Layers of air shield us from killer rays and solar wind, but magnetic storms and the aurora prove there's contact
Stormy Weather: The Sun-Earth Connection
Just as it effects weather on Earth, the Sun is responsible for
disturbances in our space environment as well.
Besides emitting a continuous stream of
solar wind, the
Sun periodically releases billions of tons of matter in what are called
coronal mass ejections
. These immense clouds of material, when directed
towards Earth, can cause large
in the magnetosphere and the
Magnetic storms produce huge amounts of power - several million megawatts - more
than enough to power the United States. Magnetic storms are a series of
disturbances -- namely,
activity, increase in the
radiation levels in the inner magnetosphere, and rapid changes in Earth's
magnetic field -- caused by increased energy input from the solar wind.
Magnetic Storm Effects:
- Aurora borealis, the northern lights, and aurora australis, the southern lights.
- Radio and television interference and blackouts
- Hazards to orbiting astronauts and spacecraft
- Power Grid Failures