How Solar Activity Influences the Northern Lights

If you're planning to visit Iceland in the winter, you've likely heard about the northern lights, one of the most thrilling natural displays on Earth. But did you know these lights are directly connected to the sun's behaviour? Understanding how solar activity impacts the auroras will deepen your appreciation for them and help you plan the best time to see the northern lights during your trip to Iceland. This article will explore how the sun's energy impacts the night sky and why Iceland is the perfect spot to witness bright auroras. 

What Causes the Northern Lights?

Northern lights occur when charged particles from the sun are carried by the solar wind and collide with the Earth's atmosphere. These particles are guided by the Earth's magnetic field, funnelling them toward the poles. When they interact with gases like nitrogen and oxygen, they release energy in the form of light. The result? The mesmerising colours that swirl and dance across the dark sky.

Solar Activity is the Engine Behind the Auroras

The sun isn't static but an incredibly dynamic ball of energy. The level of solar activity changes over time, cycling through periods of higher and lower activity known as the solar cycle, which lasts about 11 years.

During the solar maximum phase, the sun is at its most active, with more sunspots (dark, cool regions on the sun's surface). More activity means more solar wind and an increased chance of intense aurora displays. Meanwhile, there are fewer sunspots during the solar minimum phase, and aurora activity is less frequent, though it still happens.

Fun Fact: The National Oceanic and Atmospheric Administration (NOAA) tracks solar cycles and provides forecasts for aurora activity. If your trip to Iceland coincides with strong solar activity, your chance of seeing the northern lights improves significantly.

Coronal Mass Ejections and Geomagnetic Storms

One of the most dramatic forms of solar activity is a coronal mass ejection (CME). These massive bursts of solar material can travel millions of kilometres through space. When a CME hits the Earth, it can trigger geomagnetic storms and disturbances in the Earth's magnetic field. Geomagnetic storms supercharge aurora activity, often making the lights brighter and more widespread. 

Why is Iceland Is the Perfect for Northern Lights Viewing?

Iceland's location near the Arctic Circle makes it one of the best places in the world to see the northern lights. The country's long, dark winters and vast open spaces offer ideal conditions for aurora hunting. While aurora activity depends on the sun, the time to see the northern lights is also critical. In Iceland, the best months are September through April, when nights are the longest and darkest.

How Can I Track Aurora Activity?

Several tools and resources can help you plan your aurora adventure in Iceland. 

Aurora Forecasts

Our Northern Lights Forecast provides real-time data on solar activity and geomagnetic storms.

KP Index

The Kp index is a common way to measure the strength of geomagnetic activity.This scale measures geomagnetic activity, with higher numbers (KP 4 or above) indicating more significant geomagnetic disturbances.

Local Knowledge

When you arrive in Iceland, check with locals or at places like Perlan in Reykjavík for tips on the best aurora-viewing spots. You can even sign up for a northern lights tour from one of several travel companies in Iceland. 

Visit Perlan to Learn More

For an in-depth look at the science behind the aurora borealis, be sure to visit Perlan in Reykjavík. This iconic attraction offers interactive exhibitions that explain the role of solar activity, solar wind, and magnetic fields in creating the northern lights.

Furthermore, Perlan's planetarium show simulates the northern lights, giving you a preview of what to expect before you head out into the Icelandic night. It's the perfect place to connect science with the awe-inspiring beauty of Iceland.

Fascinating Facts About the Northern Lights

The Colours Depend on Altitude

Green auroras are most common and occur about 100 km above the Earth, while red auroras occur higher up, at around 300 km.

Auroras Occur on Other Planets

Jupiter, Uranus, Neptune and Saturn also have auroras, thanks to their strong magnetic fields and solar wind interactions.

Legends Abound

In Nordic mythology, the northern lights were believed to be the reflections of Valkyries' shields as they guided fallen warriors to Valhalla.

FAQ

What is the solar cycle, and why is it important?

The solar cycle is an 11-year period during which the sun's activity fluctuates. Higher activity during the solar maximum increases aurora displays, while lower activity during the solar minimum reduces them. Even though aurora activity is actually higher shortly after solar maximum.

What are coronal mass ejections?

CMEs are intense bursts of solar material ejected from the sun; when they reach the Earth, they can cause geomagnetic storms, which can enhance the northern lights.

When is the best time to see the northern lights in Iceland?

The best time for a chance to see auroras is from September to April, during the long, dark nights. Check the aurora forecast for optimal activity.

How does the number of sunspots affect aurora activity?

More sunspot indicate higher solar activity that can, at times, cause strong aurora displays.

What is the KP Index, and why does it matter?

The KP Index measures geomagnetic activity on a scale of 0 to 9. A higher value means a more powerful geomagnetic storm that sometimes, but not always, leads to excellent aurora displays.

Can I see the northern lights during a solar minimum?

Yes, although geomagnetic storms are less frequent.