Not just the Earth, space weather is important too

Did you know that although we are 150 million kilometres away from the sun, intense solar activities create a ‘space weather’ condition that can severely hamper our ground and space-based technologies?

The sun is a raging, roiling mass of gases that fuse in its core. Enormous storms that arise on the sun’s surface from time to time spew highly charged particles into space that the earth’s atmosphere cannot protect against.

When the particles penetrate the ionosphere, they can induce high currents. The currents can potentially damage electrical grids, disrupt communication signals, cause satellite orbital drag and decays, hamper electronics and expose air travellers and astronauts to hazardous radiations. Hence, studying space weather, just like regular weather, assumes importance.

Although such events occurred in the past and astronomers knew the cause of solar activities, a dedicated space weather monitoring protocol emerged only a few decades ago. Space weather prediction centres keep a constant vigil on the sun with the help of ground-based sensors, imagers, satellites, and numerical weather models to assess the state of the sun in real-time. They collect data of the sun’s core, magnetosphere and earth’s ionosphere to generate pictures of the environment from the sun to earth.

Over short observation timelines, the space weather is constantly changing. It can be mild or intense depending on the activity that arises in the sun. Space weather is governed by the 11-year solar cycle. Solar and Heliospheric Observatory, Advanced Composition Explorer and India’s upcoming Aditya L1 are satellites designated to observe solar activity and help predict space weather. The solar storms take between 20 min to several hours to reach earth. Some ejections take 30 -72 hours. The prediction centres use the observation data to warn of sudden solar storms that could hamper any part of the earth.