A burst of solar activity is giving the faint possibility that the northern lights could be seen far beyond their usual range. While the odds remain slim for most people, geomagnetic disturbances from the Sun can sometimes push the aurora borealis farther south, making it visible in dozens of states under the right conditions.

The aurora occurs when charged particles from the Sun collide with the Earth’s upper atmosphere, energizing atoms and molecules and causing them to glow. Strong solar events — such as coronal mass ejections — can widen the auroral oval, increasing the area where the lights might appear. Even so, clear skies, low light pollution and a dark location are often more important for spotting faint displays than simply being within the expanded range.

For anyone hoping to catch a glimpse, timing matters. Auroras are most likely near local midnight and the hours that bracket it, when the stretch of Earth facing the incoming particles is greatest. Check space-weather forecasts and geomagnetic indices such as the Kp index, which rates global magnetic activity; values of Kp 5 or higher typically indicate a stronger chance that the lights will be visible at lower latitudes.

If you plan to look for the aurora, pick a location away from town lights and allow your eyes to adjust to the dark for at least 20 minutes. Bring warm clothing and a flashlight with a red filter so you don’t ruin your night vision. A camera on a tripod with a wide aperture and long exposure can often capture more color and detail than the eye, especially when the display is faint.

Even when the forecast suggests a possibility, appearances can be brief and subtle — a faint green band or a ripple of light low on the northern horizon. But when conditions do line up, the result can be a memorable, otherworldly show that’s worth the effort of a late-night vigil. Keep alerts from reliable space-weather services handy so you’ll know when to head outside and watch the sky.