Frequently-asked questions

What is a magnetometer?

A magnetometer is an instrument for measuring the strength of the Earth’s magnetic field. We use fluxgate magnetometers which record the strength in one direction only. To measure the magnetic field strength in all directions three fluxgate magnetometers pointing at right-angles to each other (e.g., along X, Y and Z axes) are needed.

Why make magnetic field measurements?

The strength of the Earth’s magnetic field measured on the ground is slightly disturbed by influences of the solar wind and electric currents caused by the aurora borealis. By detecting these changes we are able to provide alerts when the aurora borealis may be visible from UK.

How do I receive alerts?

You can receive alerts by subscribing to our email list, following us on Twitter or liking our Facebook page. See the AuroraWatch UK alerts page for more information.

Can I really see the aurora from the UK? Don’t I have to be in the far North (e.g., Norway, Iceland, Canada, Alaska)?

Yes, you really can see the aurora from the UK, but it is a rare event. Observers in northern Scotland might be able to see the aurora on average  6 or 7 nights per year. For southern England the frequency might, on average, be as low as only one night every two years.

Is the data still useful even when there isn’t aurora?

All of the data is useful. We need to know the expected magnetic field strength for geomagnetically quiet conditions so that we can identify disturbed periods when the aurora may be visible.