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Our planet is a giant magnet
The core of the Earth is not a permanent magnet
The motion of the molten iron and nickel creates electric currents, which produce a magnetic field-similar to an electromagnet
http://video.nationalgeographic.com/video/news/norway-aurora-borealis-vin?source=relatedvideo
Aurora Borealis
Low and High levels of auroras
Aurora BorealisThe Northern Lights are also called the
aurora borealis for Northern Dawn The Southern Lights are the aurora
australis for Southern Dawn
Solar WindsSolar winds stream
away from the sun at speeds of about 1 million miles per hour. They reach the earth, some 40 hours after leaving the sun
Magnetosphere-earth’s magnetic field
Sun FlaresOver 98% of the
charged particles from the Sun and from galactic cosmic rays that strike Earth's magnetosphere are deflected by it
But astronauts and satellites in space
are vulnerable
1859- largest auroras (solar storm recorded in history, induced electricity in the telegraph wires)Boston operator (to Portland operator): "Please cut
off your battery [power source] entirely for fifteen minutes."
Portland operator: "Will do so. It is now disconnected."Boston: "Mine is disconnected, and we are working with the auroral current. How do you receive my writing?"Portland: "Better than with our batteries on. – Current comes and goes gradually."Boston: "My current is very strong at times, and we can work better without the batteries, as the aurora seems to neutralize and augment our batteries alternately, making current too strong at times for our relay magnets. Suppose we work without batteries while we are affected by this trouble."Portland: "Very well. Shall I go ahead with business?"Boston: "Yes. Go ahead."
https://en.wikipedia.org/wiki/Aurora_australisThe aurora is the
only visible evidence that the Sun and the Earth are a
system connected by more than sunlight.
Van Allen radiation belts discovered in 1958 aka magnetosphere
The particles from the solar wind follow the lines of magnetic force generated by the earth's core and flow through the magnetosphere a teardrop-shaped area of highly charged electrical and magnetic fields.
The gases in the Earth’s atmosphere determine the auroral lights’ colors. Inthe ionosphere, where the collisions are taking place, incoming solarparticles collide with oxygen and nitrogen gases. Oxygen atoms give offgreen and red light. Nitrogen atoms give off red light. Some blue and violetlight is also given off, but it is difficult for our eyes to see it.
Why auroras are different colors