What are solar wind and solar storms?
Every day, Earth experiences weather—wind, rain, and storms. But there’s also weather in space, driven by the Sun. Two key ideas scientists talk about are the solar wind and solar storms. The solar wind is a continuous stream of charged particles, mainly protons and electrons, that blow outward from the Sun all the time. Solar storms are much bigger, temporary bursts of energy and plasma released by the Sun that can disturb Earth’s space environment when they come our way.
What is the Sun made of, and why does it matter?
The Sun is a gigantic ball of hot plasma. Plasma is a state of matter where atoms are so hot that electrons break free from nuclei, creating charged particles that conduct electricity and respond to magnetic fields. This lively, electrically charged soup roils and blasts outward with magnetic forces that shape the solar wind and events like coronal mass ejections (CMEs) — the solar storms that can reach Earth.
The solar wind: a constant breeze from the Sun
In the Sun’s outer atmosphere, the corona, temperatures soar to millions of degrees. The corona’s heat gives particles enough energy to escape the Sun’s gravity. As they stream outward, they form the solar wind, an invisible but persistent gust of charged particles that fills the space around planets, sometimes making a bubble around the entire solar system (the heliosphere). At Earth’s distance from the Sun, the solar wind can travel at incredible speeds and carries magnetic fields along with it.
How do scientists observe the solar wind?
Because you can’t see the wind itself in photographs, scientists measure it with instruments aboard spacecraft. The Parker Solar Probe is a famous mission that travels closer to the Sun than any previous spacecraft and samples the solar wind directly. It also carries a camera that helps scientists study how sunlight scatters off this solar material, much like the sky appears blue because of scattered sunlight on Earth.
What happens when solar storms reach Earth?
Earth is protected by a magnetic shield called the magnetosphere. Most of the time, the solar wind flows around Earth, thanks to this magnetic environment. However, powerful solar storms can distort and connect with Earth’s magnetic field. When the Sun ejects a large cloud of plasma — a coronal mass ejection — the interaction with Earth’s magnetism can funnel energetic particles into our upper atmosphere. This space weather can cause power outages, disrupt satellites and communication systems, and affect navigation and aviation.
Auroras: lights from space weather
Not all space weather is harmful. Some solar storms release energy that lights up the sky in brilliant auroras — the Northern Lights (aurora borealis) and the Southern Lights (aurora australis). These shimmering displays are a visible reminder of the Sun’s activity and its space weather reaching Earth.
Why do we care about space weather?
Predicting space weather helps scientists warn about possible disruptions to power grids, satellites, and communication networks. By tracking the solar wind and solar storms, researchers aim to protect technology and keep astronauts safe, while also explaining the natural wonders we can sometimes see in the night sky.
Curious about space weather?
If you’re curious about how the Sun affects our planet, you’re not alone. Scientists use satellites, ground-based observatories, and daring missions like the Parker Solar Probe to study solar wind and solar storms. The more we learn, the better we can forecast space weather and enjoy both the science and the beauty of our energetic, dynamic solar system.
