A solar storm is a term used for atmospheric effects felt on Earth from certain events that occur on the Sun (Wonderopolis, 2013). They begin with eruptions of mass and energy from the sun, in the form of solar flares, prominences, sunspots and coronal mass ejections (CMEs), etc. The eruptions involve sudden releases of stored magnetic energy, which accelerate the hot gases near the surface or in the corona of the Sun toward Earth at about 3 million miles/hr.

                                                                                                                                              

 

 

 

 

 

 

 

 

 

 

 

 

 

 

           Figure 1.1.1 - The Sun                                                          Figure 1.1.2 A Solar Storm

 

These storms seem to follow an 11-year cycle. At solar maximum, there are several ejections of energy in the Sun in a day while at solar minimum, weeks may pass between each activity.  For example, the solar storm of 1859 struck the Earth with such intensity that the northern lights were visible as far from the poles as Cuba and Hawaii (Wikipedia, 2012) and in contrast, in 2008, there were no sunspots observed on 266 of the year's 366 days (NASA, 2009).

 

The high magnetic fields in the sunspot-producing active regions also give rise to explosions known as solar flares. When the twisted field lines cross and reconnect, energy explodes outward with a force exceeding that of millions of hydrogen bombs (Redd, 2015). Radiation is emitted across virtually the entire electromagnetic spectrum (NASA).                                                                                                

SSRTs monitor very low frequency (VLF) radio waves travelling through the Earth's ionosphere. The ionosphere is a layer of the earth’s atmosphere, around 50-600 km above the earth’s surface, that is ionised by incoming UV and X-rays from the sun. It is an excellent propagator of radio waves and the increased radiation from solar flares causes the degree of ionisation to increase, strengthening the wave propagation. The radio telescope will be then able to pick up stronger radio signals, determining the increased degree of ionisation and hence, the occurrence of a solar storm.