Dunedin Aurora

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Master Display

The master display shows concise information about the space weather environment near Earth. It uses a "traffic light" system of colours to indicate activity - green is low to red is high. The following components may be displayed. If they are absent, it is because conditions are very quiet.

The Globe: This represents conditons close to the Earth. The green circle is the current reading from magnetometers located at Dunedin Aurora.

Bz: The strength of the Earth's magnetic field in an "up/down" direction. For aurora watchers, strong negative values indicate an increased liklihood for solar particals to be funnelled into our atmosphere, causing an aurora.

Ion: This shell represents the conditions in the ionosphere. GPS signals are detected at Dunedin Aurora and analysed for noise to provide this information. The ionosphere is broad but averages about 500km in height, and can be influenced by space weather conditions.

Mag: This is the condition of the magnetic field as determined by the GOES 16 satellite. This is in geostationary orbit above the east coast of the USA about at altitude of 35,780km

Density: This outermost shell is used to indicate an increase in partical density of the solar wind. This is usually an indicator of the compressed leading edge of high speed wind streams from the sun, or the impact of a coronal mass ejection.

Solar Wind Speed: The speed of the solar wind. Background levels are approx 300km/s but rise when the Earth is in the firing line of a high speed stream from the sun, or due to the effects of a CME. As a general rule of thumb, readings over 500km/s are enough to start triggering an auroral display


Magnetometers measure impacts on the Earth's magnetic field due to space weather. For the magentometers on the GOES 16 satellite and on the ground at Dunedin Aurora, we watch the rate of change. Magnetic storms that go with an auroral display cause large and rapid changes in the Earth's magnetic field.

Strong negative values of Bz are when auroral displays are most likely to be happeneing, or are at their brightest.