We captured a filaprom!

February 17, 2026February 18, 2026Photonstopper Leave a comment

*Shown in white light is our Sun as it appeared on February 4, 2026. A large sunspot, designated Active Region 4366, drew much attention as it transited the surface, issuing flares along the way.*

On sunny days, this winter, when it’s not bone-shatteringly cold, we’ve been imaging Sun. In white light, we’ve tracked the progress of a couple of impressively-large sunspots as they traversed the Solar photosphere, including one designated Active Region 4366 that drew global attention in late January and early February 2026. We’ve also been observing in hydrogen-alpha (Ha) light.

*The NOAA SWPC Solar Synoptic Analysis map showing Sun on February 16, 2026.*

On sunny February 16, we checked the NOAA Space Weather Prediction Center’s daily Synoptic Analysis map for targets of interest. Yes! The map indicated several prominences around Sun’s rim so, a great day to see what was out there.

The full-disk image of Sun as it appeared in hydrogen-alpha light. This is a monochrome image original with false color applied. The “filaprom” is located at about the four o’clock position on the disk.

While an arch-shaped prominence at about the two o’clock position was our original target, as soon as we looked through the telescope’s eyepiece we saw it — a filaprom! What’s that? The snake-like features that appear in Ha are called filaments. If a filament bridges the Solar limb, its true nature is revealed: it’s a prominence, appearing as a dark filament when viewed against the bright chromosphere, and as a bright prominence when contrasted against the blackness of space — a filaprom! It was a first for us and delightful to observe!

Close-up view of the filaprom, near the top of the arc. Lower on the curve is a prominence issued from a position just over the Solar limb. Near the left-hand portion of the frame is a filament feature — a prominence viewed against the bright Solar chromosphere.

Improvements in instrumentation and processing skills helped with both the capture and depiction of our nearest star’s activities. We recently upgraded to the relatively-new Sky-Watcher Heliostar 76Ha telescope and that has made a huge difference in visualizing the chromosphere. The telescope’s filtering system, with a “single-stack” arrangement, is capable of 0.5 Angstrom or better which really brings out detail — stronger image “signal” produces image data that are easier to process and edit. More about the telescope another time.

*The Sky-Watcher Heliostar 76Ha telescope in its parked position beneath the observatory dome.*

A little extra … domy

January 26, 2026Photonstopper 2 Comments

*The gray observatory is surrounded by accumulated and drifting snow. The dome itself wears an extra dome of accumulated snow.*

Recent arctic-air frigid weather has brought real winter weather to our region for the first time in a few seasons. Snowfall over the past 48 hours amounted to 10 or 12 inches of light, flaky, fluff. Nighttime below-zero low temperatures have erased any thought of going out; skies have been cloudy, anyway, preventing guilt and regret. So the dome remains sealed though pointed to the south for midday solar observations. If we ever see Sun again.

A break in the weather allows view of an active Sun

January 19, 2026January 19, 2026Photonstopper 1 Comment

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.

Snow, sunshine, and a nuthatch

December 15, 2025Photonstopper

*First Winter: Stella-Luna with a coating of snow, some of which is sloughing off, closed up and waiting for the occasional day or night with clear skies.*

With overcast skies, overnight temperatures of about 9°F, and five-plus inches of snowfall over the past 48 hours, we’re pretty much buttoned down. Of course, changeable as weather is, they’re forecasting sunshine tomorrow, and 47° with rain by Thursday! Yeah, you saw “sunshine” mentioned but we have a healthy level of doubt where clear skies lately are concerned. In the meantime, there is snow to shovel and birds to watch… Oh! That’s a red-bellied nuthatch!

Observatory interior showing the telescope mount without telescope, the instruments having been stowed awaiting better sky conditions. After some test runs we’re still deciding on which scope might be designated as the “permanent” observatory instrument; some shopping is also happening.

The sunspot that made the auroras

November 13, 2025December 4, 2025Photonstopper

Our inland view of the aurora borealis competing with suburban light pollution the night of November 12, 2025. The aurora *on the previous night* was stronger, raising excitement worldwide; it was cloudy here that night.

*Just above the treeline in the center of this image may be seen hints of the aurora borealis. Farther north from here, looking out over a dark landscape, the show was probably pretty good!*

Here are some views of the sunspot 
that blew off the CMEs 
that caused the geomagnetic storms
 that made the auroras 
that raised all the hubbub this week.

The sunspot at Active Region 4274 is responsible for all the action. Where we show two sunspots, the smaller one (bottom edge) is AR4275.  The first view is in hydrogen-alpha light, the second and third views are in white light; yellow-orange tones are false color applied in processing.

*Sunspots and prominences shown via hydrogen-alpha light, false color added.*

*A white light view of AR4274 (top) and much smaller AR4275 (bottom), false color applied.*

*AR4272 close up, with interesting patterns emerging in both the umbra and penumbra areas of the larger spot. Strong winds at the time of imaging reduced resolution somewhat.*

Here’s a white light image of Sun we made this morning depicting very Active Region 4274 and its less busy neighbors. Rotation is a bit off — rotated southward — but left alone for composition purposes. AR4274 is responsible for a series of coronal mass ejections (CMEs) that resulted in two nights of auroral displays that excited observers worldwide.

First snow

November 10, 2025Photonstopper

*The observatory, with a dusting of snow on its dome, sits with a background of snow-encrusted trees. Lake effect snowfall resumed after this photo was made.*

The first snow of the season arrived overnight producing, for the observatory, a beautiful daytime scene. Ground heat cleared the pavers around the structure but continued cold weather will change that — we’ll likely have to start shoveling soon. Several days of snow chances lie ahead with clear skies are expected during the day on Thursday, November 13.

Comet C/2025 A6 (Lemmon)

November 6, 2025Photonstopper 3 Comments

October 21, 2025 — It was a tough one to find but, after a good deal of effort under near-pristine (for us) skies, I was able to spot the comet C/2025 A6 (Lemmon) from a Medina County, Ohio park. This (above) is a quick edit of a single frame. Star tracking wasn’t what it should have been; I’ve got to get more practice in the field! I worked on combining multiple frames the next morning, attempting to create a better quality image.

Stacking RAW images of C/2025 A6 (Lemmon) I did what I could to pull the most out of the imagery. What we got was a somewhat “cleaner” version. Not spectacular but the best we could do given all circumstances. I hope to learn improved processing skills and revisit the source images in the future. In the meantime, though the pictures are not spectacular, I’m happy to have bagged another comet. After all, how many of them do most of us see in a lifetime? These were recorded the night of October 20 but the UTC time conversion moves the date to the 21st.

*Stacked image of Comet C/2025 A5 (Lemmon), October 20, 2025*

*A SkySafari chart showing the position of Comet C/2025 A6 at about 7:30 PM EDT, October 20, 2025, as viewed from Northeastern Ohio.*

Clear night, Moon bright

November 5, 2025Photonstopper

November 3, 2025 — The air was still and the moon so bright and clear tonight, we had to open up the observatory long enough to take a peek and a pic! Moon was 92% illuminated in its waxing gibbous phase, lighting the landscape around us, no flashlight required. Technical: Askar 103 APO telescope, TeleVue Powermate 2X Barlow, Canon EOS 5D Mk. 4 DSLR, single exposure.

It fits! Pretty much.

November 5, 2025Photonstopper

October 20, 2025 — So how well does the Meade LXD75 6-inch achromat fit under the dome? Actually, pretty well! Shooting the sun this afternoon was (outside of seeing conditions) not bad. The scope is about four feet in length, not counting imaging and observing add-ons, and the objective end swings well inside the dome. Access to the eyepiece and camera was good. Not much room to get past the visual end, however, so we’ll see! Main thing is, it fits. Pretty much.

Recent Solar adventures

October 5, 2025February 17, 2026Photonstopper

A full-disk image of Sun, as recorded in hydrogen-alpha light. Visible are two large sunspots, several serpentine filaments, and prominences that appear around the star’s limb. Credit: Stella-Luna Observatory / James Guilford

October 3, 2025 — We had been having quit a lot of trouble lately, recording data and reproducing images of Sun with prominences. There was some early success but even those images were a struggle to produce. Taking a look at suggested camera settings found in an article on solar imaging, one thing stood out — gain! We had nudged the camera’s gain setting upward and that’s not helpful and certainly not recommended; the setting should be very low or even zero! A few adjustments in data capture parameters was all it took to make a big difference in image processing and results!

Sun’s northeast quadrant, as recorded in hydrogen-alpha light. Visible are several filaments, as three prominences appear along the star’s limb. The “peach fuzz” appearance of the edge of the solar disk is caused by the presence of innumerable spicules or small prominences.

We’re very pleased with Barlow-boosted views, shown here, though we’re still having some issues with achieving even lighting across whole-disk views — just can’t seem to get them tuned right with the Coronado SolarMax III. Visual observing was also very good, especially with the TeleVue 10mm eyepiece. October 3 conditions: Clear sky, temperature of 74°F, light southeast wind.