A solar tsunami was the key to calculating what researchers from University College London have said are the first accurate estimates of the Sun’s magnetic field. The top video, called “Magnetism Revealed,” is beautiful footage of some of the solar explosions in question.
In a statement released on Thursday, UCL Mullard Space Laboratory’s Dr. David Long, the lead author of the research, said:
“We’ve demonstrated that the Sun’s atmosphere has a magnetic field about ten times weaker than a normal fridge magnet.”
Unlike earth tsunamis, the solar tsunamis are waves that are created in the course of massive explosions or flares called coronal mass ejections (CMEs). The wave travels at high speeds through the sun’s atmosphere. However, their shape and speed can be influenced by magnetic fields.
The solar tsunami was observed both by NASA’s Solar Dynamics Observatory and the Japanese Hinode spacecraft. The UK-led instrument that obtained the data was located on the Japanese craft.
In the past, the sun’s magnetic field strength has been estimated because it is so difficult to measure. However, the new measurements taken during the tsunami with three highly sensitive telescopes allowed the team to calculate the density of the solar atmosphere that the tsunami was traveling through. The three telescopes measured visual, X-ray, and ultraviolet light.
And, in turn, those measurements allowed them to calculate the actual strength of the earth’s magnetic field.
Dr. Long and his colleagues will publish their results in the journal Solar Physics.
While we’re on the topic of solar flares, the Solar Dynamics Observatory channel is one of the better YouTube channels out there. You could lose hours on a visit, but I’ll just sneak in one more cool video for now. This one shows four solar flares going off in 48 hours:
CMEs are fun to look at. And now we know that solar tsunamis can contribute to science too.
[photos by NASA/Solar Dynamics Observatory]