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
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.
An International Observe the Moon Night promotional graphic. Credit: NASA
Note: The observatory construction is essentially complete with only a few “touch up” items and further outfitting remaining. We’ll eventually get around to writing and illustrating the story of the project. First, though, the 2025 International Observe the Moon Night….
October 4 marked International Observe the Moon Night (IOMN), an event billed as an opportunity to “unite people across the globe in a celebration of lunar observation, science, and exploration.” Coordinated and promoted by NASA, IOMN boasted 1,045 registered events worldwide. That count does not include informal events and individuals who, on their own, observed Earth’s Moon, encouraged by the promotion. Unfortunately, due to a U.S. government shutdown, NASA staff are unable to update the IOMN website and we may never know how it went this year.
While we did not host an outreach event, we did post fresh, new telescopic images depicting lunar details, along with descriptions of those events as our participation. This year, we concentrated our efforts on the Threads social media platform. What follows is what we posted.
Here’s a nice full-disk view of Earth’s Moon, one we made a few months ago with a phase very close to what we see tonight. The phase is called the “waxing gibbous” and is seen between the First Quarter and Full Moon. Moon will reach its full phase the night of October 6, this year.Mare Humorum, aka Sea of Moisture, is the dark circle at the center of this image. It was formed in an impact by an asteroid or comet, the crater filled with basalt. The “sea” is about 264 miles across and is seen here near the terminator — the dividing line between night and day — not long after local lunar sunrise. Crater Gassendi is the circular ring that intersects with Humorum. The crater is about 69 miles in diameter; a smaller crater at its northern edge is called Gassed A.
Followup Edit: Spellcheck was convinced we meant to type “Gassed” when what we really wanted was Gassendi A. Maybe it was the chili we had for dinner. Here’s crater Tycho, prominent even in the heavily-bombarded southern lunar highlands. Estimated to be 108 million years old, Tycho is about 53 miles in diameter but easily spotted using binoculars or a small telescope. The crater’s vast field of ejecta rays — the spray of material “splashed” out when an object hit Moon — is bright and forms lines that lead back to their origin. The feature was named after Danish astronomer Tycho Brahe.Also near the terminator, in Moon’s northwest, is this beautiful pair of craters: Kepler (left) and Copernicus. Like Tycho, Copernicus is marked by the prominent lines of ejecta radiating from the impact site, a crater about 58 miles in diameter. Crater Kepler, about 20 miles wide, lies to the west of Copernicus with its western rim shining brightly in the light of the lunar sunrise. For our final image of the night, we’re posting our image of a complex area of Moon at the northern end of the terminator. In the upper right we see crater Anaxagoras and surroundings glowing brightly, contrasted against the stark blackness of space. The smooth band spanning the image is Mare Frigoris. “C” shaped arch marks Sinus Iridum, opening to Mare Imbrium. Crater Plato is the circle with a smooth, dark floor in the lower right. Notice the chain of smaller, satellite craters next to Plato.
Crater Plato is about 63 miles in diameter and about 3.84 billion years old. Once again, see how the western rims of the craters along the terminator shine in the low-angle light from the rising Sun.
We hope you have enjoyed what you have seen and will see online tonight, or were fortunate to attend an International Observe the Moon Night event in person. Outdoors, at home, online, or wherever you may be, we’re glad to have had you with us. We hope IOMN has united people across the globe in a celebration of lunar observation, science, and exploration, under one sky, appreciating one Moon. Goodnight, and keep looking up!
Our neighborhood star: The Sun. Photographed in hydrogen-alpha light, this image shows the roiling chromosphere of our star with a large filament parallel with the left-hand edge of the picture, sunspots strung vertically across the center, and a good number of prominences along the rim, glowing against the dark background of space. Image has been rotated — east is up, north is right. Imaged 2024-10-26. 18:43 UTC. Credit: James Guilford, Stella-Luna Observatory
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.
Our temporary observing setups are assembled on the base/floor of the planned observatory. The light orange bucket, at center, protects an empty electrical conduit that will provide utility power to a permanent pier that will be installed there. In the foreground is a table supporting a light shield for the laptop computer. The large tripod next to the table supports the white light imaging scope. In the background is the Sky-Watcher SolarQuest mount with our Coronado hydrogen-alpha solar scope attached.
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.
From an unusual vantage point, a picture of the solar setup used today to record the passage of active region 4079 toward Sun’s horizon. The red object is the planetary camera.
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.
The sun as it appeared at 11:32 AM EDT on May 10, 2025. Sunspot/Active Region numbers are labeled in this image with AR4079 very near the solar western limb or edge.
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.
A closeup view of the sunspot at AR4079. There is a bright line splitting the dark central umbra of the sunspot, the gray penumbra radiating in filaments around it. White cloud-like areas surround the sunspot, especially to its north; called plage, they are associated with areas of concentrated magnetic field.
The Sun, as it appeared on April 17, 2025, in hydrogen-alpha light. The image was recorded using a Coronado solar telescope, a Sky-Watcher SolarQuest mount, and a ZWO ASI 678MM camera. Photo by James Guilford.
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.
The Sky-Watcher SolarQuest mount is shown here aiming our Coronado 60mm hydrogen-alpha solar telescope at Sun.
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!
A business-class jet airplane trailing twin contrails is seen in silhouette against the roiling surface of the sun. The image is recorded in hydrogen-alpha light. Photo by James Guilford.
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!
Only a few minutes from occultation, Mars is seen just off the lower edge of the lunar limb in this full-disk image recorded at 9:09 PM EST. The event only occurs with planet Mars about once every 14 years. Photo by James Guilford.
Clouds held off — pretty much — for us to observe the Moon occult* Mars, the reddish dot in the photo above. About once every 14 years or so, everything lines up just right and planet Mars is hidden by Earth’s Moon. Though Mars is about twice as big in diameter as our Moon, it was nearly 60 million miles farther away from Earth during the encounter — to the unaided eye, Mars looked like a tiny bright red star next to the Full Moon.
As predicted by mathematics, Mars and Moon grew nearer and nearer each other until, at 9:12 PM Eastern Standard Time (EST), the Red Planet disappeared behind our brilliant orb.
Mars, the small reddish dot in this image, nearing occultation by Earth’s Moon, as seen at 9:07 PM EST, January 13, 2025. Photo by James Guilford.A red arrow indicates a ghostly mound that was Mars as it disappears behind Earth’s Moon at 9:12 PM EST, January 13, 2025. The dark oval to the right of Mars’s vanishing point is the lunar basin Grimaldi. Photo by James Guilford.
Passing clouds threatened to obscure the event but thanks to gaps between those clouds, there was enough clearing for observation. Shortly after Mars vanished, so did those inter-cloud gaps. With Moon now cloud-covered, we did not return to the 13℉ night to watch for Mars to emerge.
Technical: Canon 6D Mk. 2 Camera, Canon 400mm EF 1:5.6 L Lens, Canon 2X telextender, ISO 400, f/11, 1/250 second, photographic tripod.
*Occult: To cut off from view by interposing something. Commonly used as a noun to indicate something supernatural that is hidden from ordinary access.
The complete solar disk as recorded in hydrogen-alpha light. The “worm-shaped” shadows seen in several areas are filaments. The dark spots are, yes, sunspots. And around the rim or limb of the solar disk are seen prominences — geysers of solar plasma riding magnetic field lines before crashing back into the sun. False color applied.
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.
Using a Barlow lens to zoom for a closer view, we see large and small prominences and hints of spicules along Sun’s limb, and several large filaments. The dark spots in the upper left-hand corner of this picture is a group of sunspots at active region 3889.
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.
Using a Barlow lens to zoom for a closer view, we see large and small prominences and spicules along Sun’s limb. The dark spot just above the center of this picture is a large sunspot at active region 3879.
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.
The complete solar disk as recorded in hydrogen-alpha light. The “worm-shaped” shadows seen in several areas are filaments. The dark spots are, yes, sunspots. And around the rim or limb of the solar disk are seen prominences — geysers of solar plasma riding magnetic field lines before crashing back into the sun. Image was recorded and presented here in monochrome.
C/2023 A3 (Tsuchinshan-ATLAS) seen against a starry night sky on the night of October 17, 2024.
C/2023 A3 (Tsuchinshan-ATLAS) has faded so very much in just a few days! We wish that we could have seen it early in the week — right after it became an evening object here — but rain and clouds ruined the first nights and, as I just said, that comet is fading *fast* as it retreats toward the outer regions of our Solar System. Comet C/2023 A3 had what seemed to be an extraordinarily long tail and, while we were unable to capture its extent, you can see hints of it leading far beyond its bright nucleus. Visual sightings, for us, were binocular-assisted only and when we could finally see it, C/2023 A3 wasn’t exactly “spectacular”but it was another comet to add to our “life list”.
C/2023 A3 (Tsuchinshan-ATLAS) the night of October 18, 2024, seen above moonlit, autumn-colored trees reflected in still lake waters. Photo by James Guilford.C/2023 A3 (Tsuchinshan-ATLAS) the night of October 18, 2024. Photo by James Guilford.
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!
The area in the upper left-hand portion of this photograph is AR3848, the “active region” that produced an enormous solar flare on October 8, 2024. This is a view of Sun in hydrogen-alpha light, which shows the solar coronosphere layer. Photo by James Guilford.
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.
During peak activity, looking east, we see intense red crowning a curved green ring, the Northern Lights reflected from the surface of still lake water. Photo by James Guilford.
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.
The western end of the coronal arc appeared strongest, as viewed from Medina County, through most of the evening. Here, during the surge, we see typical auroral colors, curtain-like waves of shape, and pillars that look like they reach the ground or might be mistaken for searchlights projecting from the ground. Photo by James Guilford.
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.
Although some observers were concerned that moonlight might drown out the aurora, that was not a problem during the peak or as it began to subside. This image shows the waxing Moon, low to the western horizon, with colorful patches of glowing sky nearby. Photo by James Guilford.
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.
NOAA Space Weather Prediction Center graphic showing the predicted extent of the October 10-11, 2024 aurora borealis. Observers reported seeing portions of the aurora as far south as the Florida Panhandle. According to SpaceWeather.com it was seen as far south as Puerto Rico!
Stella-Luna Observatory 