Friday, January 4th 2013, 11:33 AM EST
The peak of this year's eleven-year cycle of the Sun, is likely to be the lowest of the last century. And 'the arguments of NASA scientists who observe our daily star. The number of sunspots is extremely low, despite the short and the expected maximum of its activity. In addition, the radio waves, known to be indicative about solar activity, are very small. "The current cycle, known as Cycle 24," says Joe Gurman, NASA Stereo Project scientist.
"The interest, however, should not diminish as a single flare can damage power grids and knock out satellites, as has happened many times in the past," says the scientist. Although solar science is still in its infancy, has made significant strides in recent years, especially after the incident of Quebec in 1989, when a strong geomagnetic storm produced an extended blackout in Quebec.
"The frequency with which these phenomena occur, however, is much lower than the current widespread outages that occur due to snow storms or hurricanes, as happened recently with Sandy," said Gurman. Galileo Galilei was the first observer of sunspots, but the first reliable records date back to 1849, when the 'Observatory of Zurich began daily observations.
Sunspots are areas of the surface cooler than the surrounding areas, which by contrast appear darker. You notice usually above or below the equator and the cause of their formation is the interaction between the solar plasma and the surface magnetic field. In some circumstances, the twist of the magnetic fields generates enormous explosions that are defined flares, capable of generating huge coronal mass ejections towards space. The charged particles and the plasma clouds emitted, they head from time to time to our planet.
Fortunately, our magnetic field protects us from the electromagnetic radiation generated by these phenomena, acting as a sort of anti-missile shield. So we can sleep soundly.