science – The Amazing Sky

September 1, 2026September 1, 2026

Chasing the Earth-Shadowed Moon to the Mountains

August was a fine month for eclipse chasing, ending with the last major lunar eclipse for many years — and a trip to catch it from a scenic site.

Two eclipses in two weeks! On August 12, 2026 I was in Spain to see the total eclipse of the Sun. My report on that successful expedition with the Capture the Atlas tour group is here.

Two weeks later, on August 27, the alignment of Sun, Earth and Moon was still in effect, producing a major eclipse of the Moon. The Full Moon passed into the Earth’s dark shadow, called the umbra, turning the Moon deep red.

Solar and lunar eclipses always come in pairs, two weeks apart. But the lunars associated with a total solar eclipse are usually either barely visible penumbral or minor partial eclipses. Having a major lunar eclipse paired with a total solar is rare, and seeing both is even rarer.

Nov. 23, 2003 total solar eclipse over Antarctica

I had to look back to November 2003 for when I last saw a total lunar eclipse and a total solar eclipse two weeks apart. And I had to travel to the ends of the Earth for a flight over Antarctica to see the latter.

However, as the chart below illustrates, the August 27 lunar eclipse was not total. At mid-eclipse about 4% of the Moon’s disk remained outside the umbra and still bright white, as that northern part of the Moon was still seeing the Sun in the lunar sky, albeit partially eclipsed by Earth.

During solar eclipses the Sun must be 100% covered to be total and to reveal all the wonders of a total solar eclipse. A 99% partial is not good enough; it is arguably just 1% of the experience.

But in a lunar eclipse, a 96% partial (as it was on August 27) is close enough to being total to show most of the effects of full total eclipse (i.e. a red Moon) that appears when 100% of the Moon is immersed in the dark umbra. So this was almost as good as a total and well worth a chase.

Picking the Site

All charts courtesy EclipseWise.com. Thank you Fred!! Click on the image to take you there.

Lunar eclipses can be seen from the half of the Earth where it is night – the white and grey zones in the map above for this eclipse. While I could have watched the August 27 eclipse from home, I decided to “chase,” not so much to seek a clear hole in clouds this time, but to seek out a scenic foreground for wide-angle shots.

I had a few sites in mind in southern Alberta. Leading up to eclipse day, forecasts consistently showed Waterton Lakes National Park in the extreme southwest corner of the province as having clear skies on eclipse night. What was worrying was the now-ever-present smoke of summer, from forest fires in B.C. and Montana. Would it be clear, but murky?

Nothing ventured …. So I headed south to Waterton hoping for the best. Upon arriving in the afternoon the sky was cloudy, but that was as forecast. Clearing wasn’t supposed to happen until the evening.

And it did! I arrived on site before moonrise to now mostly clear skies, to set up my observing gear for the evening: two telescopes — a 120mm refractor to shoot through and a 90mm refractor to look through, and a MSM Nomad tracker with a camera for wide-angle shots and a panorama with the Milky Way at mid-eclipse.

My eclipse site by day, the day after the eclipse.

The site was one I knew well from previous visits. It is the Maskinonge viewpoint on the prairie overlooking the wetlands below, and with a view toward the Rocky Mountains and peaks around the Waterton townsite to the south.

The site is a sacred place to the local Siksikaitsitapi (Blackfoot) people who have performed annual rituals here for hundreds, if not thousands of years. The Full Moon tonight was the litamatapapittssko Moon — the “Moon when leaves change colour.” Below is an illustration of all 13 Blackfoot Moons, in a display at the Waterton Lakes Visitor Centre.

But tonight the Moon itself was going to change colour.

Shooting the Eclipse

The Moon rose amid retreating horizon cloud, but soon cleared the cloud bank for telescopic close-ups with the initial partial phase underway. (Click or tap on images to bring them up full screen.)

The partial lunar eclipse with the Moon rising in eclipse. In a single 1/5th second exposure with the Askar AP120 telescope at its native f/7 focal ratio for 840mm focal length, and with the Canon R5 at ISO 200.

The rising Full Moon had a dark bite taken out of its bright disk, a bite that would grow larger as the Moon entered more deeply into the umbra.

The Full Moon in partial eclipse rising over Maskinonge Pond. In a blend of two exposures: a long 3.2-second untracked exposure for the sky and ground, blended with a short 1/4-second exposure for the Moon. Both with the RF15-35mm lens at f/2.8 and 35mm, on the Canon R at ISO 200.

The scene with the partially eclipsed Moon casting a golden “glitter path” onto the water made for a striking scene I hadn’t planned on. But the wide lens (at 35mm) nicely captured the view and the iridescent clouds around the Moon.

As the Moon entered more deeply into the umbra the moonlight diminished and what would have been a bright moonlit night turned dark with the summer Milky Way revealed to the west over Vimy Peak.

This is a 180º panorama taking in the red eclipsed Moon, at left, and the Milky Way and galactic core, at right, over the Maskinonge wetlands in Waterton Lakes National Park. All exposures for both ground and sky were 30 seconds at f/2.8 with the Canon RF15-35mm lens at 24mm, on the astro-modified Canon R at ISO 6400. The Moon comes from a blend of 8 shorter tracked exposures.

This was the panorama I was after and that dictated the site.

It is a blend of exposures taken near mid-eclipse about 10:15 pm MDT — untracked for the ground, tracked for the sky, plus shorter exposures for the Moon’s disk itself, to better portray the scene as the eye saw it. As good as today’s cameras are, they still cannot record the high dynamic range of brightness of a lunar, or solar, eclipse. Shooting and blending multiple exposures is still required.

I had to make last-minute changes to settings, opting to shoot at a much higher ISO (6400) than I normally would, to keep exposures short (30 seconds each for the main ground and sky segments), due to Waterton’s infamous winds buffeting the camera. The wind was calm for most of the evening, but of course picked up at mid-eclipse!

Mid-eclipse in a blend of 7 exposures from 1/8-second to 8-seconds with the Canon R5 at ISO 100, on the Askar APO120 refractor at its native f/7 for 840mm focal length.

Having shot the panorama, I turned my attention to the telescope, which I had been using over the previous hour and a half to shoot close-ups of the ever-increasing partial eclipse.

But I wanted a set taken close to mid-eclipse. Again, the great range of brightness from the sunlit side to the shadowed Moon called for a range of exposures, seven in this case (what the Canon R5 camera can shoot automatically), from 8 seconds down to 1/8 second.

The longest exposure picked up the faint stars of Aquarius surrounding the Moon, with Sigma Aquarii at lower left the brightest; it was obvious in the eyepiece of the visual telescope. That scope showed the subtle blue-grey tint along the edge of the Earth’s shadow, from sunlight filtering through the ozone layer in our upper atmosphere.

This is a composite illustrating the passage of the Full Moon through the northern portion of Earth’s umbral shadow. The sequence runs from right to left, as the Moon moved west to east through the shadow and against the background stars of Aquarius.

I kept shooting with the telescope, to capture the final partial phases. I wasn’t so ambitious as to shoot every few seconds for a time-lapse. I did that at a similar eclipse in September 2015 and the result is here on YouTube.

This time I shot enough frames to create the composite above, showing the progress of the Moon through the umbra, as it moved from west to east against the stars, right to left here with north up.

As a result the Moon “draws” Earth’s large circular umbral shadow it is moving through. The effect was particularly pronounced at this eclipse, with the Moon passing along a chord across the northern portion of the umbra, which out at the Moon’s distance is three times the diameter of the Moon, as you can see above.

A deep total eclipse with the Moon moving through the centre of the umbra would not have been as effective at revealing the circular shape of the umbra in such a composite. I was glad to have had clear skies this night! Because …

When is the Next Eclipse?

The next such “red Moon” (a full total eclipse) is not until December 31, 2028. But we don’t see it well from Alberta, as the Moon sets at dawn just as totality begins. Eastern North America sees nothing of that coming eclipse; Asia and Australia are the favoured areas to see it (in white below) on New Year’s Day, January 1, 2029.

The Americas are poorly placed for the next total lunar eclipse.

Then, as shown below, we have a run of two more total lunars six months apart in 2029: on June 26 and December 20. But neither of those is well-placed for western Canada. As the charts below show, locations much farther east are the places to be.

For my area, the next major lunar eclipse, a total, that we see well in its entirety, is not until October 8, 2033 (as below). Another seven years!

There’s a “tetrad” of four total lunars in a row in 2032-33, but we in western Canada see only the last in the series, charted here.

We’ve been spoiled of late, with a string of total lunars in recent years visible from here — just in the last 18 months we’ve had two: on March 3, 2026 (shot from home), and on March 14, 2025, which was another Waterton eclipse I blogged about here.

The other links below will take you to my reports on earlier lunar eclipse adventures, as most have required a chase to find clear skies on cloudy winter, spring and autumn nights. The August 2026 event was the first summer (i.e. warm!) lunar eclipse I’d seen since 2007.

But for my area we are entering a seven-year lunar eclipse drought, with the eastern hemisphere about to have their turn enjoying the coming lunars.

A self-portrait of the triumphant eclipse chaser. In a single 8-second exposure at f/2.8 with the RF15-35mm lens at 15mm on the Canon R at ISO 6400.

Just like total solar eclipses, seeing a total lunar eclipse before 2033 (at least for me) will require travel to far off locations. I’m willing to chase some, but not all, total solars. I’m not so sure about total lunars!

So this might have been my last deep red Moon for quite a while. But it was a good one with which to end my lunar eclipse chases … for now!

— Alan, September 1, 2026 / amazingsky.com

April 30, 2025April 30, 2025

Touring the Constellations of Spring

Join me in a guided tour of the famous (and not so well known!) constellations of the northern spring sky.

The northern spring sky lacks the splendour of bright patterns such as winter’s Orion or summer’s Cygnus, but it is still well worth getting to know. The Milky Way is out of sight, and in its absence we are left with fewer bright stars to dazzle us at night. But we are treated to the year’s best views of famous constellations such as Ursa Major, Leo and Virgo.

Now, I am talking about the sky of the northern hemisphere, where April and May brings spring, and places the Big Dipper high overhead. While some of these constellations can be seen from the southern hemisphere, they appear to the north, low and “upside-down” from the views I present here. And April and May are autumn months.

Let’s start with the “big picture.” (Tap on images to bring them up full screen.)

NOTE: I shot all these images during a run of fine nights in mid-April 2025 with a 15-35mm zoom lens on a Canon EOS R camera, and on a Star Adventurer tracker. Separate exposures through a Tiffen Double Fog 3 filter added the star glows.

This image, in labeled and unmarked versions, presents a wide view of the spring sky from horizon to well past the zenith overhead. The key pattern to look for is the Big Dipper, at its highest in northern spring. In the UK and Europe it is known as the Plough or Wagon. Look way up to find it first.

Its Pointer Stars in the Bowl famously point north to Polaris. But here I show the other pointer line off the Bowl, to the south, to Leo the Lion. It is well known as one of the constellations of the Zodiac. Leo is marked by one of the brightest spring stars, Regulus.

Use the Handle of the Dipper to arc downward, to locate the brightest star of spring, Arcturus, shining with a yellow light. Keep that line going south and you’ll come to a dimmer and bluer star shining in the south. That’s Spica, the brightest star in Virgo, the Zodiac constellation east of Leo.

Now let’s take a closer look at selected areas.

This is still a wide view, looking up and high in the south. There’s the Big Dipper/Plough at top. It is not a constellation. It is an “asterism” of seven stars within the large constellation of Ursa Major, the Great Bear. With a little imagination you can join the dots to make a bear (many northern cultures did so). Except we draw him with a long tail, which bears do not have!

The paws of the Bear are marked by a trio of double stars: Alula Borealis and Australis, Tania Borealis and Australis, and Talitha and Talitha Australis. The names come from Arabic words for “first,” “second,” and “third” as these sets of double stars are collectively called the Three Leaps of the Gazelle in Arabic sky lore. Once you see them you’ll be surprised at how distinctive they are.

Below Ursa Major is Leo, a pattern that does look a little like a sitting cat. Its bright star Regulus was named by Copernicus, from a Latin word for “little king.” But Regulus has long been known as the heart of the Lion.

To the east lies brighter Arcturus, a name that means “bear watcher,” as it and its host constellation Boötes, the Bear Herdsman, are tied to Ursa Major and Minor in Greek mythology.

Here I frame Leo, but also two of the constellations that flank him: Cancer the Crab to the right (or west) and Coma Berenices to the left (or east). Each contains a bright naked eye cluster of stars:

Messier 44 or the Beehive cluster in Cancer, the faint Zodiac pattern west of Leo. When I shot this image in mid-April 2025 red Mars was just entering Cancer.
and Melotte 111 in Coma Berenices. At one time this clump of stars easily visible to the naked eye was considered part of Leo, as the tuft on the end of his tail. The area was broken off as its own constellation in the 3rd century BCE, and named for Queen Berenice of Egypt, and for her legendary hair (“coma”).
Together, the obvious pattern of Leo and the star clusters that flank him form one of the spring sky’s most notable sights.

The head of Leo is marked by a curving arc of stars popularly called The Sickle. Or it is thought of as backwards Question Mark, with Regulus the dot at the bottom. Leo is one of the oldest constellations, as there are records of this pattern dating back to 4000 BCE in Mesopotamia.

More modern is the obscure pattern above it, Leo Minor, the Little Lion. It was invented by 17th century star chart maker Johannes Hevelius, to fill in a blank area of sky. Even in a dark sky, it is tough to make out its innocuous pattern between Leo and Ursa Major.

Canes Venatici, Coma Berenices and Boötes

Another obscure pattern created by Hevelius lies below the Handle of the Big Dipper. A sparse pattern of stars marks Canes Venatici, the Hunting Dogs that belong to Boötes to help him herd bears! While not much to look at with the naked eye, Canes Venatici does have superb targets for telescopes, such as the double star Cor Caroli and very red star La Superba.

Below the Dogs lies Berenices’ Hair, home to the star cluster Mel 111, but also the North Galactic Pole (NGP). This is the point 90º away from the plane of the Milky Way and the Galactic Equator seen in our winter and summer skies. But in spring we look straight up out of our Galaxy, to many other telescopic galaxies that inhabit Coma and Virgo, our next stop.

Below Leo and Boötes lies the Zodiac pattern of Virgo, usually thought of as the reclining Greek goddess of agriculture and the harvest. Spica is easy to see, but the sprawling pattern of the rest of Virgo is not so obvious. It takes a dark sky to pick out the other fainter stars of the goddess.

Easier to see, despite its low altitude from northern latitudes (it skims my horizon), is the quadrilateral pattern of Corvus the Crow, a constellation that dates from the 2nd century CE and the star catalogue of Ptolemy. The Crow sits on the tail of Hydra the Water Snake, a long zig-zag line of stars that is only partly contained here. The head of Hydra, off frame to the right here, is in the earlier image of Leo and Cancer.

Another pattern riding the back of Hydra is Crater the Cup, associated with Corvus and Hydra in a Greek myth in which the Crow is sent to fetch water for Apollo but fails. Apollo flings the Crow, Cup and Snake into the sky. Angering the gods could get you immortalized in the sky!

Heading back north above Virgo, we return to the kite-shaped pattern of Boötes above Arcturus, the brightest star in the northern half of the sky. Coming up later on spring evenings, and to the left is a semi-circle of faint stars, the Northern Crown, or Corona Borealis, another of Ptolemy’s patterns from the 2nd century. The crown belongs to the princess Ariadne.

Astronomers have been watching Corona Borealis closely in recent months, waiting for a recurrent nova star to explode and add a new jewel to the Crown. So far, no luck. T CorBor remains stubbornly dim.

To the east of Corona is the H-shaped pattern of Hercules, the Roman name for the Greek hero Heracles. Among his many labours and conquests, he slewed Cancer the Crab and Leo the Lion.

Returning down south and scraping the horizon from my northern latitude late on spring nights are the next two constellations of the Zodiac east of Virgo: Libra the Scales and Scorpius the Scorpion.

Libra is a faint pattern but with the wonderfully named stars Zubeneschamali and Zubenelgenubi, meaning the northern and southern claws, as these stars were once considered part of the Scorpion. However, Libra has long been seen as a balance or scales for meting out justice. It is the only Zodiac constellation that is an inanimate object.

Scorpius is one of the few patterns that looks like what it is supposed to be, though here I see only the northern part of the constellation. His curving tail has yet to rise as the Milky Way comes into view low in the south just before dawn this night. The bright orange star is Antares, the heart of the Scorpion, set in an area rich in dark and colourful nebulas.

The appearance of Scorpius signals the return of the Milky Way to the sky, and the rise of the summer constellations.

But no astronomical life is complete without getting to know the patterns of spring. Clear skies and happy stargazing!

— Alan, April 30, 2025 (amazingsky.com)

December 9, 2024December 20, 2024

The Great Comet Chase of 2024

A plan to shoot the promised bright comet of 2024 paid off, with fine views at dawn and at dusk of the best comet since 2020.

Comets are always a gamble. Any new comets discovered, the ones that usually become the brightest, have no track record of performance. Predictions of how bright a new comet might appear are based on what a typical comet should do. But comets can outperform expectations and dazzle us, or they can fizzle and fade away.

In late 2023 it was clear that a then newly-discovered comet, C/2023 A3, named Tsuchinshan-ATLAS after the observatories where it was co-discovered, had the potential to perform in late 2024.

The low angle and position of the comet from home in Canada in the late September dawn sky, simulated in StarryNight software.

Knowing where it would be in the sky (that trait of a comet can be predicted with accuracy!) I planned a field trip to the U.S. desert Southwest for late September and early October 2024. From farther south the comet would be higher than it would be from home (shown above), and over spectacular landscapes.

I had visions of another Comet NEOWISE from July 2020. As my blog from 2020 shows, we saw that photogenic comet well from our northern latitude in Canada, as it skimmed across the northern horizon. Tsuchinshan-ATLAS would require a chase south.

September 26 & 27 — at Bryce Canyon, Utah

In late September 2024 the comet would be inbound, approaching the Sun and in the morning sky. What better eastern scene than overlooking Bryce Canyon in Utah, where I had been a year before, for the October 14, 2023 annular eclipse of the Sun in the morning sky. (Click the link for my eclipse chase blog.)

I was fortunate to get two clear mornings, both from the Fairyland Canyon viewpoint, just a short walk from the parking lot to carry camera gear and tracking mounts.

Comet C/2023 A3, Tsuchinshan-ATLAS, at dawn over Bryce Canyon, on the morning of September 27, 2024.

My first look at the comet on September 27 was on the day the comet was at perihelion, closest to the Sun in its orbit, though not in the sky at our viewing angle from Earth.

The comet was just visible to the unaided eye, but was obvious on the camera view screen, even amid the bright twilight. I had to shoot fast as the window between “comet rise” and the sky brightening too much was only a few minutes long.

Comet C/2023 A3, Tsuchinshan-ATLAS, rising in the twilight over Bryce Canyon, on September 28, 2024.

Knowing better what to look for, I caught the comet a little sooner the next morning on September 28, and so the tail appeared longer and more impressive as it rose above the distant mountains. A group of other local photographers arrived just a few minutes too late both mornings, and so struggled to just sight the comet, let alone photograph it.

This vertical panorama takes in the nebula-rich northern winter Milky Way over the formations of Bryce Canyon National Park, from the Fairyland Canyon viewpoint.

But I had arrived extra early, to shoot a vertical panorama (above) of the winter Milky Way over the canyon formations below. This and the comet images were shot with the aid of a sky tracker to follow the stars, but with the tracker off for separate shots of the ground.

So I had bagged the comet at Bryce! On to the next stop.

September 28 & 29 — at Monument Valley, Utah

There’s no more iconic or famous landscape in the American West than the buttes of Monument Valley, on the Navaho Tribal Lands on the Arizona/Utah border.

This panorama from the Navaho Tribal Park at Monument Valley shows the evening twilight sky looking east opposite the sunset to the rising dark blue arc of Earth’s shadow cast on the atmosphere. The shadow is rimmed with a pink “Belt of Venus” tint from sunlight still hitting the upper atmosphere.

A clear first evening provided a fabulous view of the arc of Earth’s shadow across the eastern sky from the viewpoint near the aptly named The View Hotel.

This is a panorama of the sunrise scene at the Navaho Tribal Park, Monument Valley, Arizona, taken just after sunrise with the low Sun lighting the iconic buttes and mesas of the Valley. The West and East Mittens are at left; the Sun was behind Merrick Butte at centre, and lighting Mitchell Mesa at right.

A wonderful sunrise on my second morning there made for a spectacular panorama. But while clouds created fine sunrise lighting, they aren’t conducive to seeing comets!

Comet C/2023 A3, Tsuchinshan-ATLAS (at centre), is rising in the dawn twilight over Monument Valley, Arizona on the morning of September 30, 2024. The comet is rising just south (right) of Merrick Butte.

A band of clear sky near the horizon allowed me to catch the comet rising to the right of Merrick Butte, as seen from a spot south of The View from where I had calculated the comet would rise in the right position. From the usual Valley viewpoint farther north the comet would have been behind the butte.

While the planning worked, the result was not quite the spectacle I had envisioned. The comet was nice, but was starting to become lost in the bright sky as it descended toward the Sun.

There were only a couple of mornings left to catch the comet at dawn before it disappeared completely into the daytime sky close to the Sun.

October 1 to 11 — at Quailway Cottage, Arizona

The major block of time in my trip was booked for an astrophoto retreat at a cottage I’d rented twice before but not since late 2017. The Quailway Cottage, popular among birders, is also ideal for stargazing as it is in one of the darkest areas of the Southwest, north of Douglas, Arizona, and just across the Arizona/New Mexico border.

This captures both the glow of Zodiacal Light in the eastern dawn sky (the band of light extending up across the frame) and the dust tail of Comet Tsuchinshan-ATLAS rising from behind the Pelloncillo mountains, at dawn on October 2, 2024.

When I arrived the comet was putting in its last show in the dawn sky. In fact, on October 2 I managed to capture a dawn scene with the morning Zodiacal Light created by sunlight reflecting off cometary dust in the inner solar system, and just the tail of the comet rising before the bright comet head appeared.

Comet C/2023 A3, Tsuchinshan-ATLAS, is rising in the dawn twilight over the Pelloncillo Mountains in New Mexico, on October 2, 2024.

An image taken a little later showed the entire comet, now sporting a more impressive tail. It was blossoming into a fine comet indeed. But we were about to lose sight of it for more than a week.

Arizona Deep-Sky Imaging

While at Quailway I had clear skies every night. And so, as planned, I went to town shooting all kinds of “deep-sky” objects and fields with two astrophoto rigs I had brought with me: a longer-focal length 120mm refractor for small targets, and a short-focal length refractor for wide fields in the Milky Way. I had reviewed both new telescopes in recent months.

The Askar APO120 on a veteran Astro-Physics AP400 mount.

I concentrated on shooting targets low in the south that are impossible to get from home in Canada, and that I’ve missed shooting, or have not shot well, during my visits to Australia. See my blog here about my latest trek Down Under.

The two brightest Fornax cluster members are the elliptical galaxy NGC 1399 at upper left, paired with smaller NGC 1404, and the galaxy NGC 1365 at lower right, considered one of the best barred spirals in the sky.

Here’s an example, above, with the larger Askar 120APO: a field of galaxies in the constellation of Fornax that rivals the better-known Markarian’s Chain of galaxies in Coma Berenices in the northern spring sky.

This frames the spectacular region of the Milky Way near the direction of the galactic centre in Sagittarius.

And here’s a field (above) with the small Founder Optics Draco 62mm scope, framing the rich Sagittarius Starcloud punctuated with the small dark Ink Spot Nebula, all below the bright Lagoon and Trifid Nebulas.

This panorama extends for about 240º along the northern half of the Milky Way, from Orion at left, to Sagittarius at right, and centered on the Galactic Equator.

In autumn the Milky Way is up all night. So I used a simple star tracker, the MSM Nomad reviewed here on my blog, and a 28-70mm lens at 35mm to shoot a panorama from dusk to dawn along the Milky Way — from the summer stars of Sagittarius and Cygnus (at right, above), through the autumn constellations overhead in Cassiopeia and Perseus (at centre), and down into the pre-dawn sky with the winter stars in and around Orion (at left).

A Bonus Aurora from Arizona

I was just north of the Mexican border, at a latitude 32° North, more than 20° farther south than at home in Alberta. But what should appear in my sky but … aurora!

A selfie of me observing the great red aurora of October 10, 2024, from southern Arizona.

On October 9, and then again more so on October 10, a great solar storm brought Northern Lights down to me. And indeed across all of Canada and the U.S. The result for me was a red glow to the north — the tops of distant auroral curtains I would have seen filling my sky at home.

A time-lapse of an Arizona aurora, using a 15mm wide-angle lens shooting nearly 400 forty-second exposures. View it in-line here. Enlarge to a full screen view. There is no sound.

Above is a time-lapse video of the aurora that night, from a camera aimed due north for four hours. The red curtains come and go through the night.

This is a 360° panorama covering the entire sky and extending up to the zenith at centre, capturing a rare SAR arc across the Arizona sky in the pre-dawn hours of October 11, 2024.

The remarkable feature that night, October 10/11, was not the aurora, but what is called a SAR (Stable Auroral Red) arc that persisted all night. It appeared as a diffuse red band across the sky, created by heat energy leaking into the upper atmosphere during the solar storm. SAR arcs can accompany an aurora but are not auroras themselves.

This panorama takes in a rare confluence of skyglows in a colourful dawn sky.

By dawn the next morning, now October 11, the tall Zodiacal Light was prominent alongside the magenta SAR arc to the north (left) and the winter Milky Way to the south (right). There’s even a short pillar of light that might be an aurora fragment, or the tail of the comet!

The Comet Returns

However, toward the end of my 11-night marathon of deep-sky imaging, the bright head of the comet was to be rising into the evening sky for Part 2 of its apparition. Below is a shot from the evening of October 11, my last at Quailway. Yes, there it was, just above the Chiricahua Mountains. But it was a blip, barely visible in binoculars and to the camera. I had hoped for more.

This is Comet Tsuchinshan-ATLAS (C/2023 A3) at far right, barely visible emerging into the evening sky and low in the twilight, on October 11, 2024. This view includes Venus at left. Venus was obvious; the comet was not!

With the Moon now waxing into the evening sky, my plan was to head back north, stopping at scenic spots on the trip home, to catch the comet over moonlit landscapes to the west in the dusk sky.

My first two nights, October 12 and 13, at the VLA Radio Observatory near Socorro, New Mexico, then farther north near Canyon de Chelly, Arizona, were both beset by clouds to the west. From images posted on-line, I knew the comet was improving. But it was eluding me.

October 14 & 15 — at Arches National Park, Utah

The next stop was Arches National Park in Utah, which I last visited in April 2015. The first night’s forecast for October 14 also looked to be cloudy. But October 15 was supposed to be clear. So I extended my stay by an extra night, thinking that might be my only chance.

As it turned out October 14 was fabulous (below). The comet was easily visible to the unaided eye as a classic comet in the west. I pointed it out to folks walking by at the Windows Arches area. And I could hear other people commenting on it. At last a comet! One that anyone could see — though it helped to be at a clear sky site like Arches.

Comet Tsuchinshan-ATLAS at its finest in the evening sky, two days after its closest approach to Earth, and with it sporting a 10º- to 15º-long dust tail, and a narrow anti-tail pointed toward the horizon.

By then the Moon was well advanced in age to a bright gibbous phase, so the sky was by no means dark. It was deep blue in photos.

Still the comet showed up brilliantly; it had blossomed a lot in a couple of nights. Above, I framed it beside moonlit Turret Arch.

Below is a scene from the next night, October 15, my “back-up” night. The comet was certainly performing well after all. Even in the moonlight. In binoculars the tail stretched for the same length as the camera recorded it, some 15°.

This is a telephoto close-up Comet Tsuchinshan-ATLAS over the red rocks of Arches National Park, Utah, on a superb moonlit night, October 15, 2024.

Indeed, that was my last view of the comet for a while, as clouds prevented any more shooting on the rest of my journey north through Idaho and Montana. I even hit a snowstorm in southern Montana.

Late October — Back at Home in Alberta

But the comet was not done yet! Through October, while it receded from us in distance, it climbed higher into our sky, placing it into a dark sky with the Moon now out of the way.

This is Comet Tsuchinshan-ATLAS in a wide-angle nightscape scene over the Badlands of Dinosaur Provincial Park, Alberta, on October 23, 2024.

On October 23, a short trip out to Dinosaur Provincial Park east of home allowed me to shoot the comet over the Alberta Badlands landscape, beside the setting summer Milky Way.

This is a telephoto lens framing of Comet Tsuchinshan-ATLAS in Ophiuchus on the night of October 30, 2024 near several large star clusters. The field of view is 15º by 10º so the tail extends for about 6º to 8º.

By a week later, on October 30, the comet had diminished in size and brightness, but still looked like a classic comet, here framed in a telephoto close-up as it passed near some bright star clusters. This was from my front yard. The chase was over.

Clouds and a trip to Norway starting November 4 prevented more opportunities to shoot the comet. (My travel schedule also kept me from writing this blog until now!)

It had been a good chase over a month, yielding images I was happy with. The photos from Utah and Arizona I could not have taken at home, even if the skies had been clear during the comet’s prime-time. (They weren’t!) And it was great to finally get back to my favourite haunts in southern Arizona and New Mexico after an absence of seven years.

In all, Comet Tsuchinshan-ATLAS provided a fine finale to what has been a superb year of stargazing events and celestial sights.

— Alan, December 9, 2024 — AmazingSky.com