Weather in space is controlled by the Sun’s activity. The solar wind, a gaseous stream composed mostly of electrons and protons, constantly flows from the Sun’s
outer atmosphere into the solar system. Earth is protected from the solar wind’s direct effects by the magnetosphere, the outermost part of Earth’s atmosphere. However, when the Sun’s
activity peaks, there are dramatic effects on Earth. Massive solar flares, coronal mass ejections, and other events on the Sun trigger space storms. These events vary in frequency and
intensity with the 11-year solar cycle.
|Space storms can cause satellites to fail and disrupt communications on Earth. An extremely powerful space storm caused
failure of the electric power system in the Canadian province of Quebec in 1989. In 2001, Earth was spared the direct effects of the most powerful solar flare ever recorded because it
was directed away from Earth.
Auroras that are visible in areas other than the polar regions of Earth indicate the severity of space storms. Auroras occur when some of the charged particles in the solar wind penetrate
Earth’s magnetosphere and strike hydrogen, nitrogen, and oxygen atoms and molecules in Earth’s atmosphere. These atoms and molecules emit light. Auroras generally occur around Earth's
north and south geomagnetic poles in regions known as auroral ovals. An aurora in the southern hemisphere is aurora australis; in the northern hemisphere, aurora
The color of an aurora depends on the identity of the atoms or molecules struck by the charged particles.
The brilliant all-red auroras are due to high-altitude oxygen atoms that have been bombarded by high-energy electrons. Oxygen atoms at lower altitudes produce brilliant yellow-green
auroral lights. Ionized nitrogen atoms produce blue auroral lights, and neutral nitrogen molecules produce red. Purplish-red auroral borders occur when the colors from nitrogen mix.
| (0.0K)||Atomic oxygen emits green light with a wavelength of 557.7 nm and red light with a wavelength of 630.0 nm when electrons
return to lower energy states after bombardment by high-energy electrons. Determine the frequencies for both the green and red lights produced.|
| (0.0K)|| Determine the energy of one photon of the auroral lights produced by oxygen atoms.|
| (1.0K)|| Useful Web Sites:|
The National Space Weather Program