Spectacular Northern Lights Could Return as Potentially Historic Extreme Solar Storm Unfolds

Skies across the United States lit up Tuesday night with unusually vivid northern lights that were visible as far south as Florida and Texas after two coronal mass ejections (CMEs) struck Earth. The activity produced a Severe (G4) Geomagnetic Storm — level 4 out of 5 on NOAA's Space Weather Prediction Center (SWPC) scale — and forecasters warn that the storming may continue through the week.

Tuesday's G4 storm and what was seen

Active regions on the Sun launched waves of charged particles that produced bands of green, red and purple aurora across the night sky. While auroras are normally confined to polar regions, the strength and orientation of this event allowed the lights to spread well beyond the poles. Observers in the Southeast reported faint purple glows (often enhanced by smartphone cameras), while the Midwest and Northwest saw bright overhead red aurora.

The intensity and direction of the storm meant some viewers saw auroral light in multiple directions rather than the usual northerly arc.

More geomagnetic activity expected

SWPC forecasters say another CME is expected to arrive Wednesday, and geomagnetic activity is likely to remain elevated through Wednesday night into Thursday. Models show the potential for another G4 period with a chance of escalating to Extreme (G5) conditions — levels not seen since last May’s global aurora event. If activity remains high after sunset, auroras could again appear at unusually low latitudes.

Possible impacts on technology and operations

Strong space weather can affect power grids, satellites, GPS signals and radio communications. SWPC reported that Tuesday’s event produced a “wide-area blackout of HF radio communication for about an hour” when it peaked near 5 a.m. ET. Under severe conditions, power systems may experience voltage control issues and spacecraft operators can face tracking and drag complications.

The heightened activity also affected launch plans: Blue Origin announced a postponement of the New Glenn launch that had been scheduled to carry NASA’s ESCAPADE spacecraft to Mars, citing concerns about elevated solar activity and potential impacts on the mission. Blue Origin said they will assess alternative launch windows as space weather and range availability allow.

Note: SWPC has notified operators in the power, radio and satellite communities to help them mitigate potential impacts.

How to view the aurora

Under normal conditions, faint auroras are best seen under dark skies away from city lights. During severe or extreme storms, however, auroras can sometimes be visible even over well-lit urban areas — downtown observers in Chicago, Boston and Denver reported glows on Tuesday. For viewers farther south, choose dark, open locations. When the display is faint, use a camera or a smartphone’s night mode or long-exposure settings to reveal colors that may be hard to see with the naked eye; Florida photographers used long exposures to capture delicate purple hues during Tuesday’s event.

If you plan to photograph the aurora, use a tripod, wide-aperture lens and exposures of several seconds to capture faint colors. Stay aware of official advisories from SWPC and local agencies if you rely on affected technologies such as HF radio, GPS or satellite communications.