Solar Maximum Arrives: Why Aurora Is Moving South

If you have noticed more photos of purple and green skies on your social media feed lately, you are not imagining it. We have officially entered the “Solar Maximum,” a period of intense activity on the Sun that is pushing the Northern Lights much further south than usual. This means people living in places like Alabama, California, and southern Europe are getting rare opportunities to witness the aurora borealis.

What Is Solar Maximum?

The Sun does not burn at a constant, steady rate. It goes through a roughly 11-year cycle of magnetic activity. We are currently in Solar Cycle 25, which began in December 2019.

This cycle has distinct phases:

  • Solar Minimum: The sun is quiet with very few sunspots.
  • Rising Phase: Activity increases.
  • Solar Maximum: The peak of the cycle, characterized by a high number of sunspots and explosive solar storms.

In October 2024, NASA and the National Oceanic and Atmospheric Administration (NOAA) confirmed that we have reached the Solar Maximum phase. While scientists originally predicted a milder cycle, Solar Cycle 25 has exceeded expectations in strength and intensity. This peak phase is expected to last through 2025, meaning we have another year or more of elevated chances to see the lights.

The Mechanism: How Solar Flares Create Auroras

To understand why the lights are moving south, you have to look at what happens on the surface of the Sun. During Solar Maximum, the Sun’s magnetic field is twisted and complex, leading to the formation of sunspots. These are cool, dark areas on the solar surface that act as launchpads for solar flares and Coronal Mass Ejections (CMEs).

Solar Flares vs. CMEs

  • Solar Flares: These are intense bursts of radiation. They travel at the speed of light and reach Earth in about 8 minutes. They can cause radio blackouts but do not directly cause the aurora.
  • Coronal Mass Ejections (CMEs): These are massive clouds of solar plasma and magnetic fields hurled into space. This material travels slower, usually taking 15 to 72 hours to reach Earth.

When a CME slams into Earth, it interacts with our planet’s magnetosphere. This collision dumps energy into our atmosphere, exciting oxygen and nitrogen gases. When these atoms return to their normal state, they release energy in the form of light (photons), creating the aurora.

Why The Lights Are Visible Further South

Normally, the aurora is confined to the “Auroral Oval,” a ring centered around the magnetic poles. This usually covers high-latitude regions like Alaska, Canada, Scandinavia, and Iceland.

However, during a strong geomagnetic storm caused by a CME, this oval expands toward the equator. The stronger the storm, the further south the oval pushes.

The G-Scale and Kp Index

Scientists use the G-scale to rate geomagnetic storms, ranging from G1 (Minor) to G5 (Extreme). They also use the Kp Index, which ranges from 0 to 9.

  • Kp 3-4: Visible in Canada and Alaska.
  • Kp 5-6 (G1-G2 Storm): Visible in northern US states like Michigan or Maine.
  • Kp 7-9 (G3-G5 Storm): The oval expands significantly.

During the historic geomagnetic storm on May 10, 2024, Earth experienced a G5 (Extreme) storm. This was the strongest storm since 2003. As a result, the aurora was photographed as far south as Florida, Puerto Rico, and Mexico. This is exactly what Solar Maximum brings: more frequent and more powerful CMEs that push the viewing line into mid-latitude regions.

How to Spot the Aurora During Solar Maximum

Seeing the lights requires more than just a solar storm; you need the right conditions on the ground.

1. Monitor Space Weather

Do not rely on mainstream news, as they are often too slow. Use specific resources:

  • NOAA Space Weather Prediction Center (SWPC): This is the primary source for US alerts. Look for their “3-Day Forecast.”
  • Apps: Download apps like “Aurora Reach” or “My Aurora Forecast & Alerts.” These send push notifications when the Kp index spikes.

2. Find Dark Skies

Light pollution is the enemy of the aurora. Even during a strong storm, city lights can wash out the colors. You need to drive 20 to 45 minutes away from city centers. Use websites like Dark Site Finder or Light Pollution Map to find areas with darker Bortle scale ratings (ideally Class 4 or lower).

3. Use Your Camera

During Solar Maximum storms, the aurora often appears grey or like a faint milky cloud to the naked eye. This is because human eyes are not sensitive to color in low light.

Modern smartphone cameras are much more sensitive than the human eye.

  • Night Mode: Set your phone to “Night Mode” with a 3-to-10-second exposure.
  • Tripod: Keep the phone steady.
  • Point North: If you are in the Northern Hemisphere, face the northern horizon.

You might snap a picture of a grey sky and see brilliant purples and greens appear on your screen.

The Colors of Solar Maximum

The colors you see depend on which gas is being excited and at what altitude.

  • Green: Produced by oxygen molecules at lower altitudes (up to 150 miles). This is the most common color.
  • Red: Produced by high-altitude oxygen (above 150 miles). This is rarer and usually seen only during intense solar storms. Because of the curvature of the Earth, people in southern locations (like Texas or North Carolina) often see only the red top of the aurora, making the sky look like it is on fire.
  • Purple/Blue: Produced by nitrogen. These colors often appear at the lower edges of the display during very energetic storms.

Impacts Beyond Beautiful Lights

While the aurora is beautiful, the increased solar activity during Solar Maximum poses challenges to technology.

  • GPS Issues: The disturbed atmosphere can delay satellite signals, causing GPS errors of several yards. This impacts precision agriculture and drilling operations.
  • Satellite Drag: The atmosphere expands during solar storms, increasing drag on low-earth orbit satellites. SpaceX has previously lost Starlink satellites due to this density increase.
  • Power Grids: Geomagnetically induced currents can flow through power lines, potentially damaging transformers. Grid operators monitor space weather closely to offload stress during G4 and G5 storms.

Frequently Asked Questions

When will Solar Maximum end?

While we are currently in the peak, the “maximum” phase is a plateau rather than a single day. Scientists expect high activity to continue throughout 2025 and possibly into early 2026 before the cycle begins to wane.

Is it safe to be outside during a solar storm?

Yes. The Earth’s magnetic field and atmosphere protect humans on the ground from the harmful radiation associated with solar flares and CMEs. The danger is strictly to technology and astronauts in space.

Why do the lights look better on camera?

Human eyes use “rods” for low-light vision, which see in black and white. Cameras have sensors that can accumulate light over several seconds (long exposure), allowing them to capture the saturation and color that our eyes miss in the dark.

Can I see the aurora from my backyard?

If you live in a city or bright suburb, probably not. Unless it is a G5 event like the one in May 2024, you usually need to travel to a location with low light pollution to see the structure and movement of the lights.