A break in the weather allows view of an active Sun

Full disk image of Sun as viewed in hydrogen-alpha light. Snake-like, dark filaments grace the center of the image. Several sunspots are also noted. Dominant in its influence on surrounding plasma features, is Active Region 4341 which exploded with a powerful flare one hour after this image was recorded.

With recent weather, we believed the observatory might be closed until spring. On January18, however, the skies were clear and blue with very little wind. We unsealed the dome, brushed off some of the accumulated snow, and aimed at Sun. The first thing we observed was the presence of large filaments at the center of the disk. One filament, Z-shaped, was in immediate proximity to a large sunspot at Active Region 4341. Also visible were multiple prominences around the disk; Sun is still active! The powerful magnetic forces surrounding AR4341 are made evident by its influence upon Solar plasma — twisting and aligning the visible features like iron filings around a science classroom magnet.

A close-up view of Solar Active Region 4341, in hydrogen-alpha light. Snake-like, dark filaments grace the center of the image. Several sunspots are also noted. Dominant in its influence on surrounding plasma features, AR4341 exploded with a powerful flare one hour after this image was recorded.

While the sky was clear and blue, the temperature was wicked cold for standing around on stone floors. Also, touching metal telescopes, properly allowed to reach the ambient temperature of 19°F, with bare hands is, painful. The laptop computer also found the temperature uncomfortable for, while its battery was charged to about 60% capacity, the system quit complaining of low battery. Attaching the computer’s charger let us finish the session.

Video from NASA's Solar Dynamics Observatory spacecraft, showing the X1.9/3b flare at AR4341. -- January 18, 2026. The Solar image appears in shades of green with black background. The flare is at the center, in white, as it expands during the explosion.
Video from NASA’s Solar Dynamics Observatory spacecraft, showing the X1.9/3b flare at AR4341. — January 18, 2026

One hour after we recorded the images of AR4341, the sunspot exploded with a massive X1.9-class flare. Expansive auroral displays are expected early January 20 though here, in Northeast Ohio, we are expecting cloudy, winter weather.

Also appearing on Sun, sunspots at AR4347, 4342, and 4344, shown here in white light (false color applied), in the northern hemisphere. Hydrogen-alpha light reveals features in Sun’s chromosphere, whereas white light imagery shows features, such as sunspots, in Sun’s photosphere — a layer deeper.

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