Northern lights visible across parts of the Chicago area
The aurora was visible to observers in parts of the Chicago region on Tuesday night and into early Wednesday morning, with viewers sending vivid photos from South Barrington, Oswego, Joliet, Huntley and other suburbs.
What caused it: Space weather forecasters reported several coronal mass ejections (CMEs) from the sun that were expected to reach Earth late Tuesday and into early Wednesday. Those eruptions can trigger geomagnetic storms that light up the night sky and, in stronger cases, briefly interfere with radio, GPS and power systems, according to the National Oceanic and Atmospheric Administration (NOAA).
Local forecasts and viewing window: ABC7 Chicago AccuWeather meteorologist Cheryl Scott and meteorologist Tracy Butler said auroras could still be visible on Wednesday in the predawn hours, though predicting the strength and exact timing is difficult. Butler noted that observers sometimes get only an hour or less notice before a visible display.
"The sun is near the peak of its roughly 11-year activity cycle, which makes auroras more frequent and widespread," said meteorologists monitoring the event.
The sun is currently in an active phase of its 11-year cycle, increasing the likelihood of colorful displays appearing farther from the poles. Skywatchers across the United States and Europe have seen auroras at unusually low latitudes in recent months.
Impacts beyond the lights: When fast-moving solar particles and plasma strike Earth's magnetic field, they can do more than create beautiful skies. Severe geomagnetic storms can temporarily disrupt power grids, affect satellite operations and scramble radio and GPS signals. Historical examples include the 1859 event that produced auroras as far south as Hawaii and damaged telegraph systems, and a 1972 storm that may have detonated magnetic naval mines off Vietnam.
Space-weather agencies such as NOAA and NASA warn that long-range forecasting of specific solar storms is limited. Instead, officials issue short-term alerts so utilities, airlines and satellite operators can take precautions as an outburst approaches. NASA and NOAA expect the sun's elevated activity to continue at least through the end of the year, though the exact timing of the peak is often confirmed only months later.
Viewing tips: For the best chance to see aurora, find a dark spot away from city lights, face north, and watch the sky in the hours before and around local sunrise when meteorologists say visibility is most likely.
Photos and reports were provided by ABC7 viewers across the suburbs. Associated Press contributed to this report.
