Auroral Electrojet Index
Measure the currents that power the aurora.
Pxie's auroral electrojet index tracks the electric currents flowing high above the polar regions, computed from ground magnetometer stations.
Plan: Builder plan.
Coverage: Global, with stations in northern Europe, the United States, New Zealand and Antarctica. Canada is not covered yet. Detail is highest close to a station.
What Auroral Electrojet Index gives you.
Upper, lower, combined and mean indices
The four standard electrojet indices (AU, AL, AE and AO) from auroral-zone ground stations, so you can see when currents surge. Values update every few minutes from the latest station readings.
A southern hemisphere electrojet view
Indices are computed separately for the northern and southern hemispheres. The southern view is built from Antarctic ground stations and currently uses a single station, so it is an indication of southern activity rather than a full ring around the pole. Few sources offer a southern view at all, which makes it useful for research and for aurora apps serving the southern lights.
Computed by Pxie, and what that means.
Computed by Pxie
This is not an official published index. Pxie computes it from live ground magnetometer readings using its own station set and baselines, so values will not match the figures published by other services. Treat it as Pxie's own measure of how strongly the auroral currents are flowing.
Northern view
The northern indices use eleven stations in Alaska and Finland. They cover two of the four longitude sectors around the pole, so activity over the other sectors is only partly captured. Canada has no stations in the network yet.
Southern view
One Antarctic station feeds the southern index today, and the response states how many stations and longitude sectors were used. More southern stations would improve it.
Best used for
Research, dashboards and aurora apps that want a live gauge of auroral activity, and for tracking how a night develops. For a decision about your exact location, use the local storm level instead.
What the four indices show
The upper index tracks the strongest eastward current, the lower index the strongest westward current, the combined index the total spread between them, and the mean index the average level. When currents surge during a burst of aurora, the lower and combined values climb sharply.
How often it updates
Values refresh every few minutes from the latest station readings, and each response lists which stations were used, so you can judge how much weight to give it at any moment.
Why a southern view matters
Almost nothing is published for the southern hemisphere. Even a limited southern index lets apps serving the southern lights, and researchers comparing the two poles, see activity that would otherwise go unmeasured.
Related
Northern currents surging
Southern hemisphere steady
"How active is the magnetic field near Tromsø right now?"
Pxie answers with the get_local_kp tool. Space weather MCP server →
Auroral Electrojet Index questions.
What is the auroral electrojet index?
A measure of the strength of the electric currents flowing in the auroral zone, which rise sharply during aurora bursts.
Is there a southern hemisphere electrojet index?
Yes. Pxie computes the indices for both hemispheres separately.
What does it cost?
It is included from the Builder plan.
Track auroral currents in both hemispheres.
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Developers: Auroral Electrojet Index docs →