Spectacular Northern Lights Expected Across the US Due to Severe Geomagnetic Storm
The National Oceanic and Atmospheric Administration (NOAA) has issued a G4 (Severe) geomagnetic storm watch for January 20, which could result in stunning displays of the northern lights across much of the United States. This rare event occurs when a coronal mass ejection (CME) from the Sun interacts with Earth's magnetic field, creating the aurora borealis.
What Caused This Rare Phenomenon?
The storm was triggered by an R3 (Strong) solar flare that erupted from a sunspot region near the center of the solar disk on January 18. This flare accompanied a CME that is expected to arrive at Earth as early as late January 19 Eastern Standard Time or early January 20.
The Science Behind the Lights
Auroras occur when charged particles from the Sun collide with gases in Earth's atmosphere. These collisions excite oxygen and nitrogen molecules, causing them to emit light. The colors we see—typically green, pink, and sometimes purple—depend on which gases are struck and at what altitude.
In this case, the CME is carrying a significant amount of solar material that will compress Earth's magnetosphere, enhancing the intensity of the auroral displays. Normally visible only in northern latitudes, a G4 storm could make the northern lights visible as far south as the southern United States.
When and Where to Look for the Aurora
Forecasters expect the geomagnetic storm to peak on January 20, though effects may be noticeable beginning late on January 19. The aurora could be visible starting around local dusk and continuing into the night hours.
Best Viewing Locations
For optimal viewing, find a location away from city lights with clear skies. The northern horizon will offer the best perspective. Areas with less light pollution include national parks, rural areas, and designated dark sky sites.
While the storm is classified as G4, actual conditions could range from G1 to G3 upon initial CME arrival, meaning visibility might vary. Conditions may persist through January 20 before gradually weakening, with G1 levels possible on January 21.
Potential Impacts Beyond the Beautiful Lights
Geomagnetic storms of this magnitude can have effects beyond creating beautiful auroras. According to NOAA, possible impacts include:
- Power grid fluctuations that may require corrections
- Interruptions in high-frequency radio communications
- Navigation system accuracy issues
- Possible impacts on satellite operations
While these effects are typically managed by utility and communication companies, the storm serves as a reminder of how interconnected our modern systems are with space weather.
How to Photograph the Aurora
For photography enthusiasts, capturing the northern lights requires specific techniques:
- Use a tripod to avoid camera shake
- Set your camera to manual mode with an aperture of f/2.8 or lower
- Use a shutter speed between 5 and 20 seconds
- Increase ISO to 800-3200 (experiment to avoid noise)
- Consider using a remote shutter or timer to avoid touching the camera
Remember that the intensity of the aurora will affect your settings, so be prepared to experiment.
Historical Context: Rare but Memorable Events
G4 geomagnetic storms are relatively rare but not unprecedented. The last comparable storm occurred in 2017, and before that in 2015. These events create once-in-a-decade opportunities for aurora viewing in regions that typically don't experience such displays.
The most famous recent extreme storm was the 1989 event that caused a massive power blackout in Quebec, Canada. While this upcoming storm is expected to be less severe in terms of infrastructure impacts, its auroral displays will be equally spectacular.
Stay Informed
For the latest forecasts and updates on the geomagnetic storm, visit the NOAA Space Weather Prediction Center website. They provide real-time data and forecasts that can help you plan your aurora viewing.
Remember that space weather is dynamic, so conditions may change. Clear skies and a bit of patience may reward you with an unforgettable natural light show.
