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The instantaneous distribution of auroras ("auroral oval") is slightly different, being centered about 3–5° nightward of the magnetic pole, so that auroral arcs reach furthest toward the equator when the magnetic pole in question is in between the observer and the Sun. The aurora borealis is visible from being close to the center of the Arctic Circle such as Alaska, Canada, Iceland, Greenland, Norway, Sweden and Finland.Ī geomagnetic storm causes the auroral ovals (north and south) to expand, bringing the aurora to lower latitudes. The aurora australis is visible from high southern latitudes in Antarctica, Chile, Argentina, South Africa, New Zealand, and Australia.

The southern counterpart, the aurora australis or the southern lights, has features almost identical to the aurora borealis and changes simultaneously with changes in the northern auroral zone. The former term was coined by Galileo in 1619, from the Roman goddess of the dawn and the Greek name for the north wind. In northern latitudes, the effect is known as the aurora borealis or the northern lights. Elias Loomis (1860), and later Hermann Fritz (1881) and Sophus Tromholt (1881) in more detail, established that the aurora appeared mainly in the auroral zone. Early evidence for a geomagnetic connection comes from the statistics of auroral observations. A region that currently displays an aurora is called the "auroral oval", a band displaced by the solar wind towards the night side of Earth.

Most auroras occur in a band known as the "auroral zone", which is typically 3° to 6° wide in latitude and between 10° and 20° from the geomagnetic poles at all local times (or longitudes), most clearly seen at night against a dark sky. Ancient Greek poets used the name metaphorically to refer to dawn, often mentioning its play of colours across the otherwise dark sky ( e.g., "rosy-fingered dawn"). The word " aurora" is derived from the name of the Roman goddess of the dawn, Aurora, who travelled from east to west announcing the coming of the sun.

4 Interaction of the solar wind with Earth.

2.3 Colors and wavelengths of auroral light.

Most of the planets in the Solar System, some natural satellites, brown dwarfs, and even comets also host auroras. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imparted to the precipitating particles. The resulting ionization and excitation of atmospheric constituents emit light of varying colour and complexity. These particles, mainly electrons and protons, precipitate into the upper atmosphere ( thermosphere/ exosphere). These disturbances alter the trajectories of charged particles in the magnetospheric plasma. Īuroras are the result of disturbances in the magnetosphere caused by solar wind. Auroras display dynamic patterns of brilliant lights that appear as curtains, rays, spirals or dynamic flickers covering the entire sky. Video of this encounter: Īn aurora (plural: auroras or aurorae ), also known as the polar lights or aurora polaris, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic).