auroral oval
Quick Summary
The auroral oval is a region in Earth's upper atmosphere, primarily at high latitudes, where auroras (northern and southern lights) occur. These spectacular light displays are caused by energetic particles from the Sun's solar wind interacting with atoms in Earth's atmosphere.123
When charged particles like electrons and protons from the solar wind are directed by Earth's magnetic field towards the magnetic poles, they collide with oxygen and nitrogen atoms. These collisions excite the atoms, causing them to emit radiation at various wavelengths, which we see as different colors, such as red, green, and purple.231
The auroral oval's position can shift. It moves poleward during periods of low solar activity and can expand southward to middle latitudes during intense solar activity. Auroras typically occur at altitudes between 80 and 250 kilometers (about 50 to 155 miles) above Earth's surface.231
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geomagnetic fieldField-aligned currents…are usually referred to as auroral ovals.
Read More…are usually referred to as auroral ovals.
Read More- geomagnetic fieldMagnetic reconnection
…accounts for the existence of auroral ovals. Field lines of the polar caps are “open” to the solar wind, whereas those at lower latitudes are “closed” to it, as is evident from the above figure. On the nightside the field lines connecting to the neutral line form a natural boundary…
Read More…accounts for the existence of auroral ovals. Field lines of the polar caps are “open” to the solar wind, whereas those at lower latitudes are “closed” to it, as is evident from the above figure. On the nightside the field lines connecting to the neutral line form a natural boundary…
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