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.
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!
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.
White light allows viewing Sun as if we could stare directly at it without the resulting blindness. The Herschel wedge does much the same thing but with, perhaps, a bit more contrast and detail. Both of those white light views allow us to see a layer of the solar atmosphere called the photosphere. In the photosphere the most apparent details are sunspots, standing black against a white background. With enough resolution we can also see granulation — enormous convective bubbles of searing solar plasma.
One layer above the photosphere — yes, above — is the chromosphere. Shining in the wavelength of hydrogen-alpha (Ha), the chromosphere is not visible to us without light filters that exclude all light but Ha. A wholly different view of our Sun is available in that wavelength. Swirling seas of plasma form curves and hash as they are moved by magnetic fields, long filaments float over those seas, as fountains of glowing gas arc from the solar disk contrasted against the blackness of space. On closer examination, the solar limb appears rough, a bit like a fine-toothed saw blade, as innumerable spicules, jets of glowing gas, are seen in contrast. Yes, sunspots are visible but are no longer the primary interest.
After many tries and failures at processing images to best show the chromosphere complete with prominences, I finally learned what some other imagers were using to process their images: Solar Toolbox — a package of programming scripts used with the PixInsight imaging application. I still have much to learn about Toolbox but it has already been enormously helpful to me in the challenging world of solar imaging! Thus, the image above is from very good data recorded about seven months ago, now reprocessed using Toolbox.
Monday dawned clear and bright so we set up the hydrogen-alpha (Ha) solar telescope and recorded some image sequences. Today was a dull and cloudy day so we spent some time learning new processing techniques for our solar imaging and were rewarded with our best shot yet. The processing of choice was Solar Toolbox — a script package developed for use in PixInsight software — just the set of tools we were looking for! We’ve a long way to go but we think this picture shows great progress!
We’re still doing open-air astronomy though we have a nice, solid, clean, and level space to set up our gear! This is the setup we were using today to record the sunspot at active region 4079 as it is about to roll over the solar limb/horizon. Fortunately, though it’s a very temporary setup, the portable gear we use for casual solar imaging is fairly easy to set up.
We continued experiments to determine what gear will work together for imaging. There were a few surprises and there’s need for more experimentation. What we settled on for today’s solar efforts is pictured above and includes: Askar 103 APO telescope, Meade LXD75 Goto Mount, TeleVue 2X Barlow, Baader Planetarium Safety Herschel Wedge, and ZWO ASI678MM monochrome planetary camera.
Although the sky was clear, seeing was a bit shaky so once again, sharpness wasn’t what we’d like. Still, in all, we got the shot we wanted and learned a few things about our astronomy equipment. Also, the sky was blue, the air was pleasant, and birds were singing, so not a bad way to spend a couple of hours.
Taking advantage of midday clear skies, Thursday, we set up the hydrogen-alpha telescope and did a little observing and imaging. Seeing conditions were only good but we could make out several prominences along Sun’s limb. (The proms did not record well and we need to figure out how to enhance their visibility in our images.) Most notable, however, was the shear number of filaments in Sun’s northern hemisphere. None visible in the south! Fragments of exploding filaments launched from Sun and produced two CMEs that, when they reached Earth on April 16, caused strong geomagnetic storm activity and widespread auroras. The storm, however, died out before northern lights could be seen here.
Aiding in our efforts was a device we used for the very first time in this session: The Sky-Watcher SolarQuest with its HelioFind system. The device is lightweight, easily supported our rather robust Coronado solar telescope, and was exceptionally easy to learn and operate. Essentially, all that was needed was to set the tripod up so that it was level, turn the device on, and let it do its thing! It is powered by four AA batteries, placed inside the unit. As an alt-az mount, no counterweights or muliti-axis balancing was needed; just mount the scope with its balance point at the center of the dovetail clamp. No remote control, no app, the compact and self-contained SolarQuest established GPS contact, leveled the scope, then looked for Sun. The SolarQuest turned and elevated the telescope, quickly acquiring our nearest star. When the motion stopped, we looked through the eyepiece to discover Sun well within the field of view. A few nudges of the system’s adjustment buttons and Sun was centered. Tracking was excellent throughout the observing/imaging session. Provision is made for further refinement of tracking but that adjustment was unnecessary for the day’s activity. The SolarQuest will make our daytime astronomy a whole lot more convenient and enjoyable!
We had just finished setting up for some solar astronomy and tapped the button to begin a video sequence when something flashed across the computer screen. A jet appeared for less than a second, contrails briefly persisting, silhouetted against the roiling solar disk! We’ve only seen this twice while observing Sun, this being the second time, and we only captured this image by shear luck. The first time we witnessed a solar “photo-bombing” was under similar circumstances. Previously, we had completed setup, was refining focus, and just about to begin recording exposures. We missed imaging that encounter by about the same interval as we succeeded this time!
In addition to photographing Earth’s Sun in white light nearly every clear day, we occasionally set up the heavy telescope mount and bring out the new hydrogen-alpha (Ha) telescope for a bit of visual observing and unique imaging. It’s a bit of work since, without an observatory building we usually feel we need to take down and store away the mount after each session, so we don’t do that every day.
On November 8 we had clear skies, good atmospheric conditions, and the inclination to do the Ha setup and were rewarded with splendid views plus our best Sun images yet.
Across the solar disk were visible large and distinct filaments — prominence loops seen from “above” — as well as sunspots and swirling patterns in the solar atmosphere around them. All around the Sun’s limb could be seen prominences glowing against a background of black space. Some of the prominences, which are fountain-like sprays and loops of magnetically-charged plasma, were quite large.
A major part of producing good images is what happens away from the telescope. Our usual practice is to record video of the telescope view and use software, in the office, to sort through thousands of video image frames, then stack the best few hundred to form a single still image. The still image is then edited to bring out as much detail and tonal range as possible. This process, which is common in astrophotography, produces a sharper image than what might be acquired via any single photographic “snapshot” owing largely to atmospheric turbulence.
There’s room for improvement, and we’re seeing excellent progress, but the images shown here are our best yet of Sun in hydrogen-alpha light.
Note: H-a light is that which Sun is producing in its chromosphere — the solar atmospheric layer between the outer corona and the lower photosphere — and is invisible even to protected human vision and white light cameras. Specialized optics are required to block other wavelengths found in white light and allow observation of Ha. When we observe or image in white light, we’re actually viewing features such as sunspots while looking through both the corona and the chromosphere!
Safety Note: It is not safe to look directly at the sun without specialized eye protection for solar viewing, and safe solar filters for telescope, binocular, or camera use. Permanent damage to vision can result from improper viewing of the sun.
A panoramic view of the aurora borealis as viewed from rural Medina County, Ohio, as a surge in activity occurred. The display is reflected in the still waters of a small lake. The bright light at the right-hand end above the treeline is light pollution from the city of Medina. Photo by James Guilford.
It began on Tuesday, October 8, when a sunspot called AR3848 flared explosively over the course of several hours. The detonation hurled a large and powerful coronal mass ejection (CME) Earthward from Sun. On Thursday, October 10 the magnetically-charged solar plasma hit Earth’s geomagnetic field and fireworks erupted. According to SpaceWeather.com the aurora borealis was seen as far south as Puerto Rico!
I headed out to a remote county park location, where I have permission to be after dark, and was fortunate enough to be ready when a significant surge in activity occurred — around 10 PM EDT. That peak was amazing with colors, shapes, and movement visible across the entire northern horizon. It was particularly cool to see pillars appearing and disappearing in real time. Light from the aurora reflected upon the still waters of the park’s lake. Adding to the quiet, magical mood, were occasional calls in the darkness from perched birds. A wood duck, out on the lake, piped a sound reminding me of common loons.
The auroral surge went on for probably a bit more than half an hour, challenging me to select a spot to photograph. First one area would glow, then one at the other end of the bow-shaped display, pillars of light would appear like searchlights, then fade away. A thrill to witness as light, movement, and delicate colors were visible to the unaided eye. The camera picked up more than my poor eyes could see but I say without reservation this was the grandest aurora I’ve witnessed.
All evening there seemed to be more intense activity over the western end of the aurora; that was verified by relatives in northwest Ohio whose photos showed a sky full of color directly overhead.
While I was at the lake I heard others coming and going from the park, pretty much the entire time I was there. A young couple eventually ventured away from the parking lot and encountered me at my spot around 11:30, seeking what I had found — a dark spot near the water. Their arrival had been delayed by a camera gone bad, and they had gone home to pick up another. Things petered out not long after the peak and, checking NOAA resources, it looked like the auroral ring was retreating back north. The couple had missed the best of the night and I, with frozen fingers and toes, I headed home.
Still working without a dome, our setups are outdoors and temporary so we try and keep them fairly simple. Solar observing and imaging generally lend themselves well to brief observations due to the extreme amount of light available and resultant short photographic exposures. With a couple of clear days and nights available, we took advantage and made some experiments and observations with several successive setups on a single Skywatcher EQ6-R Pro mount.
We began with the Askar 103 APO telescope and its 700mm focal length, attaching our Baader Herschel-Prism, and the new ASI678MM monochrome camera. The setup worked well but for one issue: focus was only just achieved with the focuser racked all the way in with no latitude for adjustment. Image quality was very good but probably would have been better if we’d have had a bit more inward travel. Note: It was only later that we realized we might gain the needed travel if we had switched the camera’s nosepiece from the 1.25-inch to the 2-inch, allowing removal of the thick 1.25-inch adapter ring from the Herschel. A well, duh, moment!
By the way, we continue to be impressed by the build quality and optical excellence of the Askar refractor. It’s a solid instrument with great features, delivering superb results.
The second experiment involved installing our massive Meade 6-inch telescope on the mount. The Skywatcher has a retractable rod for holding counterweights and is, therefore, a bit shorter than it might otherwise be, resulting in less leverage. It took nearly all of our available counterweights to balance the big scope. We installed the Herschel-Prism and a nice eyepiece and got beautiful views of the spotted face of our star. Attaching the ASI678MM, however, we could not reach focus — that inward focuser travel limit again — but we don’t believe the switch to the 2-inch nosepiece will help. That’s a shame! The Meade’s 1,250mm focal length would have provided amazing closeups!
With the mount set up we decided to try out the 11-inch Celestron SCT at night. Herschel wedge accessories are not to be used on reflecting telescopes as the concentrated unfiltered incoming sunlight can damage the scope’s secondary mirror. To our disappointment the telescope, which has set in storage for months since we attempted collumnation, displayed rather severe image distortions — comma-shaped stars. After a good bit of frustration we dismounted the telescope and planned to come out the next night with the Vixen Cassegrain telescope.
The following evening looked very promising; the sky was actually more transparent than it had been for the Celestron effort. Saturn would rise from behind trees neighboring our site some time after 11 p.m. so, at the appointed hour, we stepped outdoors and looked. Clouds, heralding a day or two of rain showers, were rolling in — broken at first but rapidly obscuring the entire sky. We tore down the setup, stowed the gear, and called it a night.
Over the period of a couple of days and nights, much was learned and the new planetary camera proved itself to be an excellent performer. We’ll continue to use the camera and telescope for solar and, probably, lunar views. Next we’ll likely try installing the focal reducer to achieve full-disk images.
I continued my practice of daily imaging of the sun for some weeks now. While still deciding precisely how to use and display the images I’m collecting, I’m also trying to standardize how the images are captured and establish a workflow in editing; that is in an effort to give the daily pictures the same overall size and appearance except for details, such as sunspots, where we want to observe changes. It’s not as easy as it may seem, especially when attempting to constantly improve image quality. This ought to become simpler once I have a permanent setup protected day-to-day within an observatory structure.
Sunspots AR3713 and AR3712, the more pronounced of the three large groups, have been interesting to watch as they traversed the visible side of Sun. Today (June 22), braving the morning’s already hot and humid conditions, I went to the extra work of setting up the Vixen VC200L Cassegrain telescope in an effort to achieve high quality images of the two — plus AR3716 — big sunspot groups before they disappear over the western solar limb. Both of the active regions reportedly harbor opposing magnetic energies which could, at any time, reconnect and throw off powerful flares but both have been surprisingly quiet. The next few days will be the last when an outburst from AR3713 or AR3712 might affect Earth.
Stella-Luna Observatory 