A violent solar tsunami rippling across the sun's surface has provided scientists with the first accurate measurement of the sun's magnetic field, which turns out to be weaker than your average fridge magnet.

Solar tsunamis are monstrous events, traveling around half the sun's surface in one hour at speeds up to 620 miles per hour. They were originally spotted in 1997, and are a byproduct of coronal mass ejections (CMEs), which spew stellar material and solar winds into space with such ferocity they can affect electronics and communications systems here on Earth.

"These are rare observations of a spectacular event that reveal some really interesting details about our nearest star," said Dr. David Long from the University College London's Mullard Space Science Laboratory.

Solar tsunamis move faster through stronger magnetic fields similar to how sound travels faster through water. Observations by NASA's Solar Dynamics Observatory and the Japanese Hinode spacecraft of a 43,500-mile-high tsunami traveling at 250 miles per second helped the scientists determine the magnetic strength of our parent star.

"We've demonstrated that the Sun's atmosphere has a magnetic field about ten times weaker than a normal fridge magnet," Long said.

The sun's magnetic field is of great interest to scientists because it can help explain why the sun behaves the way it does. Not only that, the sun's magnetic fields can create disruptions here on Earth through events such as CMEs.

 "As our dependency on technology increases, understanding how these eruptions occur and travel will greatly assist in protecting against solar activity."

The results will soon be published in the journal Solar Physics.