#Global magnetic field of the solar corona measured for the first time

Importantly, the speed the waves travel at depends on the strength of the magnetic field, meaning that being able to measure how fast they travel enables an estimate of the magnetic field to made.
Dr. Richard Morton, a UKRI Future Leader Fellow working at Northumbria University, is a world expert in the observation and analysis of waves in the Sun’s corona and was part of the team which delivered these exciting results.

Dr. Morton has been a long-term user of the CoMP instrument and advocate of using such measurements to study the Sun’s magnetic field. As he explains: “The data that is collected from CoMP reveals the Sun’s corona is full of these Alfvén waves and provides us with the best available view of them.”
The current research is built upon Dr. Morton’s earlier works, which demonstrated the possibility the magnetic waves could be used as a tool (Morton et al., Nature Communications 2015, Long et al., Astronomy & Astrophysics, 2017).
“I think that this is a wonderful demonstration of how we can exploit the Alfvén waves to probe the properties of the Sun,” Dr. Morton added, noting that, “the process is similar to how seismologists use earthquakes to find out what the interior of the Earth looks like.”
This is the first time that a global map of the coronal magnetic field has been obtained through actual coronal observations, thus marking a leap towards solving the problem of coronal magnetic field measurements.
In principle, with this technique, global coronal magnetic field maps could now be routinely obtained, filling in the missing part of the measurements of the Sun’s global magnetism. Together with simultaneously measured magnetic field measurements from the Sun’s surface, these synoptic coronal magnetograms will provide critical information to advance the understanding of how the magnetic field couples the different layers of the Sun’s atmosphere as well as the physical mechanisms responsible for solar eruptions and solar cycle.