This calculator was then used to convert the geomagnetic latitudes to geographic. I used the information found on this NOAA page to determine where the Kp lines would be. The shape of the auroral oval is easier to picture over a globe. A simulated view of the current auroral oval can be seen on the live data page. This is why Tasmania and New Zealand commonly see the southern lights while other continents do not.
The southern geomagnetic pole is much closer to Australia compared to Africa or South America. This explains why locations near the US-Canada border see the aurora a couple times a month on average while similar latitudes in Europe virtually never see the lights. The lights can commonly be seen from much further south in North America compared to Europe and Asia, which are further from this pole. This means that North America has a big advantage when it comes to seeing the northern lights. The geomagnetic north pole is currently (as of 2020) located at 80.7°N, 72.7°W, Ellesmere Island, Canada. It is actually centered around the geomagnetic poles, which are different from the geographic poles. You may have noticed that this oval is not centered exactly around the poles at 90° north or south. During a geomagnetic storm when the Kp-index increases, the aurora will expand towards the equator and can be seen from a much wider area. Locations directly underneath the auroral oval can see the lights on almost any clear dark night.
The auroral oval is a ring around the earth’s poles where the aurora likes to hang out. The light blue Kp0 line represents the location of the auroral oval. Aurora was seen low on the horizon over Michigan’s Keweenaw Peninsula while the Kp-index was 3. During the strongest of geomagnetic storms faint auroras have even been spotted in the southern US. This is when a camera is helpful to pick up fainter displays. But a perfect viewing location and good eyes are usually required to see it. If the Kp-index is slightly less than the line shows for a given location, the aurora may still appear low on the horizon. If the current Kp-index is greater than the line shown on the map, the aurora will often fill the entire sky. Generally once the Kp-index reaches a certain threshold it will fill the northern half of the sky (in the northern hemisphere) all the way up to the zenith along the corresponding line on the map. The map above shows you what the Kp-index needs to be to see the aurora overhead at a given location. See the current Kp-index on the Live Data page. The Kp-index is calculated by combining the data from multiple magnetic observatories around the world to determine the global planetary index. Magnetometers measure the strength of Earth’s magnetic field to determine the K-index, which is tied to a specific station. Example chart from NOAA showing a Kp8 storm A geomagnetic storm starts at Kp5 after which the G-scale is also used. The Kp-index is a scale used to characterize the magnitude of geomagnetic disturbances.
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