Solar Flare Erupts
This still from a video taken by NASA's Solar Dynamics Observatory shows the Aug. 8, 2011 solar flare as it appeared in the ultraviolet range of the light spectrum. The flare registered as an X6.9 class sun storm, the largest of the Solar Cycle 24. NASA/SDO/GSFC

By listening and monitoring sound waves around 37,000 miles above the surface of the sun, it is now possible to predict the appearance of sunspots almost two days before hand.

A group of researchers at the Stanford University has conducted a series of studies to help solar physicists understand better about solar flares and other similar space events.

The findings documented in the recent edition of Science journal provides scientists a new mode of tracking the propagation of sound waves in the solar surface and thereby improve space weather forecast.

Sunspots are magnetically active surfaces around the sun from where most of the solar flares and coronal mass ejections originate.

Moreover, the sun contains plasma which is gas stripped off one or more electrons. Turbulence created by the movement of the solar surface causes the generation of sound waves. As these acoustic waves move through the sun surface, the speed varies according to the densities of the various solar regions.

Hence, by mapping the time taken for a wave to move between two points, the density of the stuff between them can be measured.

The magnetic field of the sunspots affects the plasma on the solar surface as it is more buoyant than the churning plasma. Hence, it moves at a faster rate towards the surface and causes the sound waves to travel faster too.

The Los Angeles Times reported that the team of Stanford University researchers tracked sound-generated activity at different points on the sun's surface and found that sound waves that would normally take an hour to cross from one point to the next traveled 12 to 16 seconds faster when a sun spot was emerging.

The new research could be extremely useful for those seeking to predict space weather events like solar storms in advance and thereby enabling people to prepare for them.