Geomagnetic Storm

In News 

• SpaceX’s newest fleet of satellites is tumbling out of orbit after being struck by a geomagnetic storm.

About Geomagnetic storm

• It is also called a magnetic storm or solar storm.
• It is a major disturbance of Earth’s magnetosphere that occurs when there is a very efficient exchange of energy from the solar wind into the space environment surrounding Earth. 
• They occur during the release of magnetic energy associated with sunspots (‘dark’ regions on the Sun that are cooler than the surrounding photosphere) and can last for a few minutes or hours. 
• The material associated with these eruptions consists primarily of protons and electrons with an energy of a few thousand electron volts. 
  • This material, called plasma, moves through the interplanetary medium at speeds from less than 10 km (6 miles) per second to more than 2,000 km (1,200 miles) per second, so that the ejected material reaches Earth in approximately 21 hours. 

• The largest storms that result from these conditions are associated with solar coronal mass ejections (CMEs) where a billion tons or so of plasma from the sun, with its embedded magnetic field, arrives at Earth.
• Effect on Earth:

• They can hit operations of space-dependent services like global positioning systems (GPS), radio, and satellite communications.
• Aircraft flights, power grids, and space exploration programmes are vulnerable.

• Predicting solar storms:

• Solar physicists and other scientists use computer models to predict solar storms and solar activities in general. 
• Current models are capable of predicting a storm’s time of arrival and its speed. 
  • But the storm’s structure or orientation still cannot be predicted.

Source: IE