What is space weather? Just like the weather you experience on earth, space weather has its calm and stormy periods, too. Space weather is caused by large-scale eruptions on our sun. Those eruptions affect and interact with Earth’s own atmosphere and magnetic field.
Solar flares are sudden, explosive releases of energy from active regions on the sun. These active regions have strong magnetic fields and can show up as cooler, darker areas, seen as sunspots. Sunspots are likely areas for these solar eruptions. Solar flares release energy that travels at the speed of light, and light is so fast that it travels all the way around Earth almost eight times in just one second! When strong enough, the solar flare causes problems with radio communications like those used in airplanes flying over the oceans.
These eruptions can also accelerate charged particles at the sun, the tiny building blocks that make up every atom, creating what we call a solar radiation storm. These tiny particles can travel near the speed of light and arrive at Earth in tens of minutes to hours. These particles can also affect radio communications near the North and South Poles.
Additionally, these tiny particles can pass through satellites causing problems with the satellite’s electronics and sensors that can result in permanent damage. When these radiation storms are strong enough, they can cause an increase in radiation exposure to astronauts in space and to airline passengers in flight near the Earth’s poles.
These eruptions may also result in large parts of the sun’s atmosphere being blown into space, called a coronal mass ejection or CME for short. These CMEs can be thought of as clouds of tiny particles that together act as a giant magnet. These clouds can arrive at Earth in as little as 15-16 hours, and when they do, they cause a “jolt” to Earth’s own magnetic field resulting in geomagnetic storming. These geomagnetic storms can cause extra electric currents to flow in large power lines, in extreme cases overloading parts of the power grid and possibly causing power outages or problems. Additionally, some communication and navigation systems may become degraded, affecting things like road-building and airplane traffic.
While these storms can create such problems, they are also the driver of the spectacular northern and southern lights, or auroras. The aurora is much like a neon sign where atoms are excited and emit beautiful light. But in the case of the aurora, this sign is much bigger and high in the sky, usually near the North and South Poles.
The sun is not just our nearest star and what gives us light. It also produces a wide range of space weather that can impact the technologies we use every day.
