The Northern Lights are light phenomenon produced by the Earth's magnetic field.
They are seen from space in Gravity from orbit around Earth.
Description[]
The natural light display in the sky particularly in the high latitude (Arctic and Antarctic) regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere (Thermosphere). The charged particles originated in the magnetosphere and solar wind and on Earth are directed by the Earth's magnetic field into the atmosphere. Most aurorae occurred in a band known as the auroral zone which was typically 3° to 6° in latitudinal extent and at all local times or longitudes. The auroral zone was typically 10° to 20° from the magnetic pole defined by the axis of the Earth's magnetic dipole. During a geomagnetic storm, the auroral zone expanded to lower latitudes. Aurorae are classified as diffuse and discrete. The diffuse aurora was a featureless glow in the sky that may not be visible to the naked eye, even on a dark night. It defined the extent of the auroral zone. The discrete aurorae are sharply defined features within the diffuse aurora that varied in brightness from just barely visible to the naked eye to bright enough to read a newspaper by at night. Discrete aurorae are usually seen in only the night sky because they are not as bright as the sunlight sky. Aurorae occasionally occurred poleward of the auroral zone as diffuse patches or arcs which are generally subvisual. In northern latitudes, the effect was known as the Aurora Borealis (Or the Northern Lights), named after the Roman goddess of dawn, Aurora and the Greek name for the north wind, Boreas by Pierre Gassendi in 1621. Auroras seen near the magnetic pole may be high overhead, but from farther away, they illuminated the northern horizon as a greenish glow or sometimes a faint red as if the Sun was rising from an unusual direction. Discrete aurorae often displayed magnetic field lines or curtain-like structures and could change within seconds or glow unchanging for hours, most often in fluorescent green. The Aurora Borealis most often occurred near the equinoxes. The Northern Lights had a number of names throughout history. The Creek called this phenomenon the "Dance of the Spirits". In Medieval Europe, the auroras are commonly believed to be a sign from God. It's southern counterpart, the Aurora Australis (Or the Southern Lights) had features that are almost identical to the Aurora Borealis and changed simultaneously with changes in the northern auroral zone. It was visible from high southern latitudes in Antarctica, South America, New Zealand and Australia. Aurorae occurred on the other planets. Similar to the Earth's aurora, they are visible close to the planet's magnetic poles.
See Also[]
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