On Solstice Pond


Selfie at Solstice Pond

Solstice nights have been filled with twilights, planets, and noctilucent clouds.

Astronomers tend to curse the short nights and late sunsets of summer solstice. But the bright nights do offer unique sights.

Over the last few nights I’ve set up at what I call “Solstice Pond,” a prairie slough near home ideal for shooting the aurora to the north and, at this time of year, the glow of twilight and noctilucent clouds.

Below is the view on the night before solstice, looking north toward the glow of “perpetual twilight” that lights the northern horizon at solstice time from my latitude of 50° north.

Solstice Twilight Panorama over Prairie Pond
A 120° panorama of the summer solstice twilight (at 12:30 am local time) looking north over the prairie pond near home in southern Alberta, taken June 19/20, 2018. Some very faint noctilucent clouds are at left but fading, while some very faint rays of auroral curtains are also visible in the photo but were invisible to the eye. The bright star Capella is at centre and reflected in the calm waters. Perseus is at right of centre. The red lights at right are from the wind turbines at the Wintering Hills Wind Farm. This is a stitch of 6 segments, with the 35mm lens at f/2.5 for 20 seconds each with the Canon 6DMkII at ISO 400.

From farther north the twilight would be more prominent, while above the Arctic Circle at 66° N latitude, the twilight turns to full daylight as the Sun never sets.

The view looking south this night, with the Moon just off frame at right, includes the Milky Way at centre, with Saturn embedded, flanked by bright Jupiter at right and reddish Mars at left, both casting shimmering “glitter paths” on the still waters.

Planet Panorama at a Prairie Pond
A 160° panorama looking south near summer solstice time in June 2018, with the bright planets Mars (left) and Jupiter (right) and their glitter paths on the water flanking the Milky Way and Saturn in Sagittarius above the pinkish Lagoon Nebula. The waxing Moon is setting off frame at right brightening the sky and lighting the landscape. The sky is also blue from the solstice twilight. The stars of Scorpius shine between Jupiter and the Milky Way. Some faint bands of red and green airglow are visible at left, despite the bright sky. This is a stitch of 8 segments, all for 25 seconds with the 35mm lens at f/2.2 and Canon 6D MkII at ISO 800.

A few nights later (below), on June 24, the star of the solstice sky put in an appearance. Bright noctilucent clouds (NLCs) shone to the north, reflected in the pond.

These are water vapour clouds 80 kilometres high at the edge of the atmosphere – in the mesosphere – almost in space. They form over the Arctic in summer, and are high enough to remain sunlit even in the middle of the night as they catch the Sun shining over the pole.

Southern Western Canada – the Prairies where I live – is well-placed to see them, as we are far enough north to see them in our sky, but not so far north that our sky is too bright.

Noctilucent Clouds over Prairie Pond (June 24, 2018)
A fine display of noctilucent clouds (NLCs) or polar mesospheric clouds, reflected in a local prairie pond near home in southern Alberta. The display started with wisps much higher in the north but they faded as the Sun dropped lower, with the display at this extent by the time I reached my spot and took this panorama. Leo and Regulus are setting at far left in the west, as is Venus just above the horizon at left. Capella and Auriga are at centre, and circumpolar, while the stars of Perseus at right, rising. This is a panorama of 9 segments, at 15° spacings, with the 35mm lens at f/2.8 for 13 second exposures with the Canon 6D MkII at ISO 400. Stitched with Adobe Camera Raw.

An even better display appeared two nights later, on June 26, brighter and with more structure.

The curving arc of the top of the display defines the most southerly edge where sunlight is able to reach. That edge drops lower through the first part of the night, as the Sun itself drops lower below the horizon. This causes less of the NLC display to be sunlit.

Panorama of Noctilucent Clouds (June 26, 2018)
A panorama of a fine display of noctilucent clouds across the northern horizon over an angle of about 60°. This was on June 26, 2018 at about 11:45 pm. Capella is just left of centre. The display faded as the solar illumination dropped and the clouds darkened from the top down. This was from the small pond near home in southern Alberta. This is a stitch of 7 segments, each 2 seconds at f/2.8 with the 85mm Rokinon lens and Canon 6D MkII at ISO 400. Stitched with ACR.

You can see this effect of the changing illumination of the clouds in this time-lapse compilation from June 26 (below).

Also notice the waving motion of the clouds. It is as if the NLC material is flowing over standing waves in the atmosphere – and it is! The waves are called “gravity waves,” and are bumps in the high atmosphere created by disturbances far below in the normal layers of the atmosphere, the stratosphere and troposphere.

The video includes two clips shot simultaneously: from a camera with a 24mm wide-angle lens, and from a camera with an 85mm moderate telephoto. Expand to view full screen in HD.

The motion, here over an hour or more, is hypnotic. The NLCs move right to left (east to west), while the dark normal weather clouds on the horizon are blowing left to right (west to east). The stars are also turning left to right. The water ripples in the wind, while ducks swim by.

It was a magical night at Solstice Pond.

– Alan, June 27, 2018 / © 2018 Alan Dyer / AmazingSky.com 

 

The Moons of Lost Sleep


Waning Moon in the Morning Series (with Labels)

These are the Moons only insomniacs and night shift workers get to see. These are the waning Moons of morning.

For eight mornings I’ve been up at 4 a.m. each day to catch the early Moon and collect a series of images of its waning phases.

The result is above, a series that runs from right to left in time, from the 19-day-old waning gibbous Moon, to the 26-day-old thin crescent Moon.

I ordered them that way in the composite to reflect the direction the Moon moves across the sky. As it orbits Earth and wanes, the Moon moves from west to east, or right to left, in the sky from morning to morning, at least in the northern hemisphere.

A run of clear nights and mornings made the series possible. From Alberta, as dry as it is, too many cloudy nights make a consistent Moon phase series a challenge at best.

As it was I had to contend with smoke from forest fires in B.C. which reddened the Moon on the last few mornings, a tint I had to correct for the composite above. But here below, is what the Moon really looked like one morning.

Smoky Waning Crescent Moon
The smoky orange Moon of July 17.

The last two Moons, at 25 and 26 days old (i.e. the number of days since the previous New Moon phase) exhibited the phenomenon known as Earthshine. You can see the night side of the Moon glowing gently with sunlight reflected first off the Earth.

Waning Moon and Earthshine (July 20, 2017)
Earthshine on the 25-day old Moon on July 20 at dawn.

Below, this was the Moon this morning, July 21, with it very low in the east amid the twilight sky.

Waning 26-Day Moon with Earthshine
Earthshine on the thin 26-day old Moon on July 21 at dawn.

This final morning was exceptional. The smoke had cleared off, and when I got up at 4 a.m. (reluctantly!) for the last shoot I was greeted with the best display of noctilucent clouds I had seen in many years. They covered the northeast and eastern skies in a rare “grand display.”

Noctilucent Clouds at Dawn with the Moon and Venus
Noctilucent clouds with the Moon and Venus in the dawn sky, from southern Alberta, July 21, 2017.

The thin crescent Moon is just rising at right, with Venus bright as a “morning star” at far right. This was a sky certainly worth losing sleep over.

— Alan, July 21, 2017 / © 2017 Alan Dyer / amazingsky.com

 

Tis the Season for Night Shining Clouds


Noctilucent Clouds and Big Dipper

A bright display of noctilucent clouds last night prompts me to remind northerners to look north at this prime season for night shining clouds.

Noctilucent clouds (NLCs) can be seen only in summer and are best in the few weeks before and after (mostly after) summer solstice. I shot all these images in the middle of the night. Indeed, the two images above and just below are from 3 am on the morning of June 27.

NLCs are high altitude clouds at the edge of space some 80 kilometres above the Earth, far above any normal weather clouds. Their height allows sunlight streaming over the pole to illuminate them all night long.

Noctilucent Clouds over Pond
Noctilucent clouds at 3 am on June 27 over a prairie pond in southern Alberta. The NLCs were visible as an arc across the north for at least 2 hours and were still there as dawn twilight brightened at 3:30 am. This is looking due north with the bowl of the Big Dipper at upper left. Capella is at lower right. Shot with the 24mm lens.

Their cause is a mystery. They may form by water vapour condensing on meteoric dust particles.

They look luminescent, as if glowing on their own. But these are not auroras. They shine only by reflected sunlight.

And they have complex structures, with intricate waves and ripples.

Noctilucent Clouds (June 17, 2016)
A display of noctilucent clouds, the first good display of the season from my area of southern Alberta, on June 17/18. 2016. This is with a 105mm telephoto and the Nikon D750, and is the first frame of a 1000-frame time-lapse sequence. However, as the Sun dropped farther below the horizon the clouds did lose illumination and faded, from the top down.

And they move very slowly, as this time-lapse from June 17 shows.

Readers living at a latitude between 45° and 55° are best situated to see “NLCs.” From farther south the clouds will be below the horizon. From farther north the sky may be too bright with twilight and the angle of illumination wrong for optimum viewing.

For more information, check the Wikipedia article

Unlike auroras, there is no predicting when they might appear. Some nights when it is clear where you are, no NLCs appear. Perhaps that’s because of cloud much farther north blocking the path of light from the Sun on the other side of the planet to the clouds on our side of the Earth.

But by the end of July NLC season is coming to an end as the Sun drops farther below the northern horizon at night, and the nights get darker.

So over the next four weeks, look low in the north for night shining clouds.

— Alan, June 27, 2016 / © 2016 Alan Dyer / www.amazingsky.com 

 

Solstice Sky at Dinosaur Park


Summer solstice twilight and circumpolar star trails over the badlands of Dinosaur Provincial Park, Alberta. Some bright noctilucent clouds are visible low on the northern horizon. I shot this June 15, 2015 as part of a shoot for a “star trail” video tutorial, as an example image. This is a stack of the first 200 frames of 275 shot for a time-lapse, each 15 seconds at f/2.8 with the Rokinon 14mm lens and Canon 6D at ISO 1600. I stacked them in Advanced Stacker Actions with the ultrastreak mode. The foreground comes from a mean blend of the first 8 frames, to smooth noise, and to provide a brighter foreground from early in the sequence when the sky and ground were brighter.

The stars circle the bright northern sky at solstice time over the Alberta Badlands.

I spent the evening and well into the night on Monday shooting at a favourite spot, Dinosaur Provincial Park in southern Alberta. The result of about an hour of shooting around midnight is the circumpolar star trail composite at top.

It shows the stars spinning about Polaris, while the northern horizon is rimmed with the bright glow of all-night twilight.

Particularly bright in the northwest are noctilucent clouds low on the horizon. These are high-altitude clouds near the edge of space catching the sunlight streaming over the pole at this time of year.

Noctilucent clouds (NLCs) over the silhouette of the badlands of Dinosaur Provincial Park in southern Alberta, on the night of June 15/16, 2015. The clouds remained low on the northern horizon and faded as the Sun angle dropped through the night but then reappeared in the northwest prior to dawn. The bright star at left is Capella, circumpolar at this latitude of 50° N.  This is a single exposure for 10 seconds at f/3.2 with the 16-35mm lens and at ISO 800 with the Canon 60Da.

They are a phenomenon unique to the weeks around solstice, and for our latitudes on the Canadian Prairies.

The close-up shot above shows their intricate wave-like formation and pearly colour. They faded though the night as the Sun set for the clouds. But they returned in the pre-dawn light.

If you live at mid-northern latitudes, keep an eye out for these clouds of solstice over the next month. It’s now their peak season.

– Alan, June 16, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Night of the Noctilucent Clouds


Star Trails and Noctilucent Clouds (Lighten Stack)

It was a beautiful summer evening, with stars wheeling overhead in a moonlit sky and the only clouds far away and interesting.

This was one of those nights we get once or twice a summer when the much-anticipated noctilucent clouds – the clouds of summer – put on a perfect show. In my previous post I featured an image from early in the night, last night, June 26, 2013.

These are images and time-lapse movies from later in the night. The composite image above shows stars trailing over 90 minutes with the brilliant noctilucent clouds on the horizon, and fringed by a rosy glow of red twilight where the southern edge of the cloud display, which sits over the Northwest Territories, is being lit by a setting Sun with red sunlight filtering through our atmosphere as it passes over the North Pole.

Noctilucent Clouds and Thunderstorm (June 26, 2013)

This telephoto lens shot above captures a close-up of the rosy-fringed noctilucent clouds, behind a lightning-lit thunderstorm rolling through storm alley in central Alberta. The storms can stay there! We’ve had enough of them for a while!

 

My time-lapse sequence extends over about 90 minutes and opens with a wide-angle view of the display as it appeared low on the horizon. What follows are two closeup views that really show the intricate wave-like motion of these high-altitude mesospheric clouds, and their changing lighting and colours.

These are beautiful clouds drifting on the edge of space but it takes time-lapse to reveal their fluid-like motion.

– Alan, June 27, 2013 / © 2013 Alan Dyer

 

Time-Lapse: Northern Lights and Noctilucent Clouds


Northern Lights and Noctilucent Clouds (135mm #1) (June 9, 2013)

What strange clouds these are, moving where there shouldn’t be winds, and forming where there’s barely any air.

These are noctilucent clouds, sometimes called polar mesospheric clouds. Their icy strands form around particles at the top of the atmosphere some 80 km up. There’s almost no air up there so just how these clouds form has always been a mystery. They may be condensing around meteoric dust particles. They may also be more common now than in past decades and centuries, as the upper atmosphere cools due to an odd quirk of global warming that sees the lower troposphere warm while the upper mesosphere cools.

This was the first display of NLCs I’ve seen so far this season. They can only be seen, and indeed they only form, in summer. Sunlight streams over the pole and lights these clouds all night long. They are literally “night-shining” clouds. Only from a latitude range of 45° to 60° north and around summer solstice is the geometry right to see the clouds, usually as electric blue cirrus strands moving slowly along the northern horizon.

The time-lapse movies capture their motion over 30 to 90 minutes of shooting.

 

The 40-second movie contains three clips:

• The first, a wide-angle  view of the amazing aurora that danced in fast accompaniment to the slow noctilucent clouds.

• The second clip, very short, zooms in a little more to the northern horizon. However, I cut that sequence short so I could switch lenses and take the next clip.

• The third scene is with a telephoto lens, framing the east-to-west slow motion of the clouds. I took 4-second exposures at 1-second intervals so it shows some pretty fine motion.

This was certainly one of the best NLC displays I’d seen and my best shot at capturing them.

What was especially rare was seeing them accompanied by auroral curtains actually moving among the clouds (or so it appeared). Both are up high in the near vacuum of near space, but they may have been miles apart in latitude.

– Alan, June 10, 2013 / © 2013 Alan Dyer

Northern Lights & Noctilucent Clouds


Northern Lights and Noctilucent Clouds (june 9, 2013)

Colourful sky phenomena combine to provide a remarkable sky show.

What a night this was! On Sunday, June 9 the aurora kicked off with a burst in the bright twilight but really got going as the sky got dark, shooting beams of magenta and blue up from the main green arc.

Then on cue, streamers of noctilucent clouds appeared low in the north, shining with their characteristic electric blue. These are odd clouds at the edge of space lit by sunlight streaming over the Pole.

Both these apparitions of the upper atmosphere glowed above a horizon rimmed with the orange of perpetual twilight set in a deep blue background sky.

Yes, the camera has brought out the colours more intensely than the eye saw, but nevertheless it was a remarkable evening close to solstice. This is a magical time of year when all kinds of sky glows light the night.

This night the European Einstein ATV cargo craft also flew over, twice, each time about 10 minutes ahead of the even brighter Space Station that it is chasing for a docking later this week.

More images to come from this night, including time-lapses of the Lights and Clouds.

– Alan, June 10, 2013 / © 2013 Alan Dyer