Conjunctions, Satellites & Auroras, Oh My!


Friday the 13th Aurora Title

October has brought clear skies and some fine celestial sights. Here’s a potpourri of what was up from home. 

We’ve enjoyed some lovely early autumn weather here in southern Alberta, providing great opportunities to see and shoot a series of astronomical events.


Conjunctions

Venus & Mars in Close Conjunction #2 (Oct 5, 2017)
Venus and Mars in close conjunction in the dawn sky on October 5, 2017. Venus is the brightest object; Mars is below it; while the star above Venus is 4th magnitude Sigma Leonis. The foreground is illuminated by light from the setting Full Moon in the west. This is a single 1-second exposure with the 135mm lens at f/2 and Canon 60Da at ISO 800. 

On October 5, Venus and Mars appeared a fraction of a degree apart in the dawn twilight. Venus is the brightest object, just above dimmer but red Mars. This was one of the closest planet conjunctions of 2017. Mars will appear much brighter in July and August 2018 when it makes its closest approach to Earth since 2003.


Satellites: The Space Station

Overhead Pass of the Space Station in Moonlight
An overhead pass of the ISS on October 5, 2017, with the Full Moon rising in the east at left. The ISS is moving from west (at right) to east (at left), passing nearly overhead at the zenith at centre. North is at the top, south at bottom in this fish-eye lens image with an 8mm Sigma fish-eye lens on the Canon 6D MkII camera. This is a stack of 56 exposures, each 4 seconds long at an interval of 1 second. 

The Space Station made a series of ideal evening passes in early October, flying right overhead from my site at latitude 51° N. I captured it in a series of stacked still images, so it appears as a dashed line across the sky. In reality it looks like a very bright star, outshining any other natural star. Here, it appears to fly toward the rising Moon.


Satellites: Iridiums

Twin Iridium Satellite Flares (October 9, 2017)
A pair of nearly simultaneous and parallel Iridium satellite flares, on October 9, 2017, as they descended into the north. The left or westerly flare was much brighter and with a sharp rise and fall in brightness. While it was predicted to be mag. -4.4 I think it got much brighter, perhaps mag -7, but very briefly. These are Iridium 90 (left) and Iridium 50 (right). This is a stack of 40+ exposures each, 2 seconds at 1-second intervals, with the Sigma 24mm lens at f/1.4 and Nikon D750 at ISO 6400.

Often appearing brighter than even the ISS, Iridium satellite flares can blaze brighter than even Venus at its best. One did so here, above, in another time-lapse of a pair of Iridium satellites that traveled in parallel and flared at almost the same time. But the orientation of the reflective antennas that create these flares must have been better on the left Iridium as it really shot up in brilliance for a few seconds.


Auroras

Aurora and Circumpolar Star Trails (Oct, 13, 2017)
A circumpolar star trail composite with Northern Lights, on October 13, 2017, shot from home in southern Alberta. The Big Dipper is at bottom centre; Polaris is at top centre at the axis of the rotation. The bottom edge of the curtains are rimmed with a pink fringe from nitrogen. This is a stack of 200 frames taken mostly when the aurora was a quiescent arc across the north before the substorm hit. An additional single exposure is layered in taken about 1 minute after the main star trail set to add the final end point stars after a gap in the trails. Stacking was with the Advanced Stacker Plus actions using the Ultrastreaks mode to add the direction of motion from the tapering trails. Each frame is 3 seconds at f/2 and ISO 6400 wth the Sigma 14mm lens and Nikon D750.

Little in the sky beats a fine aurora display and we’ve had several of late, despite the Sun being spotless and nearing a low ebb in its activity. The above shot is a composite stack of 200 images, showing the stars circling the celestial pole above the main auroral arc, and taken on Friday the 13th.

Aurora from October 13, 2013
A decent aurora across the north from home in southern Alberta, on Friday the 13th, October, 2017, though these frames were taken after midnight MDT. 3 seconds at f/2 and ISO 6400 wth the Sigma 14mm lens and Nikon D750.

This frame, from some 1300 I shot this night, October 13, captures the main auroral arc and a diffuse patch of green above that pulsed on and off.

You can see the time-lapse here in my short music video on Vimeo.

Friday the 13th Aurora from Alan Dyer on Vimeo.

It’s in 4K if your monitor and computer are capable. It nicely shows the development of the aurora this night, from a quiescent arc, through a brief sub-storm outburst, then into pulsing and flickering patches. Enjoy!


What all these scenes have in common is that they were all shot from home, in my backyard. It is wonderful to live in a rural area and to be able to step outside and see these sites easily by just looking up!

— Alan, October 16, 2017 / © 2017 Alan Dyer / AmazingSky.com 

 

Northern Lights Over a Prairie Lake


Auroral Arch over a Prairie LakeThe Northern Lights dance in the solstice sky over a prairie lake. 

This was a surprise display. Forecasts called for a chance of Lights on Saturday, June 24, but I wasn’t expecting much.

Nevertheless, I headed to a nearby lake (Crawling Lake) to shoot north over the water, not of the Lights, but of noctilucent clouds, a phenomenon unique to the summer solstice sky and our latitudes here on the Canadian prairies.

Aurora and Noctilucent Clouds over Crawling Lake v2

But as the night darkened (quite late at solstice time) the aurora began to appear in the deepening twilight.

I started shooting and kept shooting over the next four hours. I took a break from the time-lapses to shoot some panoramas, such as the headline image at top, capturing the sweep of the auroral oval over the lake waters.

Aurora and Noctilucent Clouds over Crawling Lake v1

Just on the horizon you can see some noctilucent clouds (NLCs) as well – clouds so high they are lit by the Sun all night long. NLCs sit at the same height as the bottom of the auroral curtains. But they appear here lower and much farther away, which they likely were, sitting farther north than the auroral band.

Arcs of the Aurora and Milky Way
A 360° panorama of the aurora and Milky Way in the twilight sky of a summer solstice evening.

I also shot this 360° panorama (above) capturing the arc of the aurora and of the Milky Way. This is a stitch of 8 segments with a 14mm lens mounted in portrait mode.

I’ve assembled the several time-lapse sequences I shot into a short music video. Check it out on Vimeo here. Click through to the Vimeo page for more technical information on the video sequences.

As always click HD, and relax and enjoy the dancing lights over the calm waters of a prairie lake on a summer evening.

Thanks!

— Alan, June 26, 2017 / © 2017 Alan Dyer / amazingsky.com

 

Auroras from Alberta


Aurora Self-Portrait (March 2 2017)

The solar winds blew some fine auroras our way this past week. 

Oh, that I had been in the North last week, where the sky erupted with jaw-dropping displays. I could only watch those vicariously via webcams, such as the Explore.org Northern Lights Cam at the Churchill Northern Studies Centre.

But here in southern Alberta we were still treated to some fine displays across our northern sky. The image below is from March 1, from my rural backyard.

Fish-Eye Aurora (March 1, 2017)
A full-frame fish-eye lens image of the aurora on March 1 with curtains reaching up into the Big Dipper.

The Sun wasn’t particularly active and there were no coronal mass ejections per se. But a hole in the corona let a wind of solar particles through to buffet our magnetosphere, stirring up geomagnetic storms of Level 4 to 5 scale. That’s good enough to light our skies in western Canada.

Aurora over Frozen Pond
A 160° panorama of the main auroral oval to the north on March 2 about 11:40 pm MST.

Above is the display from March 2, taken over a frozen pond near home. I like how the Lights reflect in the ice.

This night, for about 30 minutes, an odd auroral form appeared that we see from time to time at our latitudes. A wider panorama shows this isolated arc well south of the main auroral oval and forming a thin arc stretching across the sky from west to east.

Aurora Panorama with Isolated Arc
A 220° panorama of the isolated arc to the west (left) and east (right) and the main auroral oval to the north.

The panorama above shows just the western and eastern portion of the arc. Overhead (image below) it looked like this briefly.

Isolated Auroral Arc Overhead
The overhead portion of the isolated arc at its peak.

Visually, it appeared colourless. But the camera picks up this isolated arc’s usual pink color, with a fringe of white and sometimes (here very briefly) a “picket-fence” effect of green rays.

Isolated Auroral Arc West
The western portion of the isolated auroral arc at its peak.

This is the view of the isolated arc to the west. Erroneously called “proton arcs,” these are not caused by incoming protons. Those produce a very diffuse, usually sub-visual glow. But the exact nature of these isolated arcs remains a mystery.

As we head into solar minimum in the nest few years, displays of Northern Lights at lower latitudes will become less frequent. But even without major solar activity, last week’s displays demonstrated  we can still get good shows.

— Alan, March 4, 2017 / © 2017 Alan Dyer / AmazingSky.com

The Sky Was Dancing


Aurora Panorama from Northern Studies Centre #2 (January 29, 201

The Northern Lights once again performed beautifully from Churchill, Manitoba, making the sky dance with colours. 

As I do each winter, I spent time in Churchill, Manitoba at the wonderful Churchill Northern Studies Centre, attending to groups of “aurora tourists” there to check an item off their bucket list – seeing the Northern Lights.

Auroral Arcs over Boreal Forest #2

In the 30 years the courses have been presented only one group has ever come away not seeing the Lights. Well, make that two now. A bout of unseasonably warm weather in my first week brought clouds every night. Mild temperatures to be sure. But we want it to be -25° C! That’s when it is clear.

Winter Star and Milky Way from Churchill Manitoba

Our first clear night was very clear, affording us a wonderful view of the winter Milky Way before the Lights came out. Such a view is unusual from the North, as the Lights usually wash out the sky, which they did later this night. Even here, you can see some wisps of green aurora.

Orion over Snow Inukshuk

Normal temperatures didn’t return until week 2 of my stay. The second group fared much better, getting good displays on 4 of their 5 nights there, more typical of Churchill.

Photographers Under the Northern Lights

A few determined die-hards from Group 1 (here shooting the Lights) stayed on a couple of more nights, and were rewarded with the views they had come for. They were happy!

All-Sky Aurora from Churchill #2 (January 29, 2017)

In the images here, at no time did the auroral activity exceed a level of Kp 3 (on a scale of 0 to 9) and was often just Kp 1 or 2. Farther south no one would see anything. But at latitude 58° N Churchill lies under the auroral oval where even on quiet nights the aurora is active and often spectacular.

Aurora Panorama from Northern Studies Centre #3 (January 29, 201

In speaking to a Dene elder who presents a cultural talk to each of the CNSC groups, Caroline said that to the Dene of northern Canada their word for the Lights translates to “the sky is dancing.” Wonderful! It did for us.

The Auroras of Churchill from Alan Dyer on Vimeo.

This music video presents a montage of time-lapse movies I shot over four nights, from January 25 to 29, 2017. They provide an idea of what we saw under the dancing sky.

As usual, choose HD and enlarge to full screen to view the movie. Or go to Vimeo with the V button.

— Alan, February 3, 2017 / © 2017 Alan Dyer/AmazingSky.com 

 

Harvest Aurora


Harvest Moon Aurora

With the harvest in full swing, the aurora and Moon lit the fields on a clear September evening.

This night, September 19, showed prospects for a good display of Northern Lights, and sure enough as it got dark a bright, well-defined arc of Lights danced to the north.

I headed off to some photogenic spots near home, on the prairies of southern Alberta. By the time I got in place, the aurora had already faded.

However, the arc still photographed well and provided a great backdrop to these rural scenes. The rising Moon, then 3 days past full, lit the foreground. In the lead image, lights from combines and trucks working the field behind the bins are at left.

Aurora and Harvest Moon at the Old Barn
A diffuse arc of aurora and the rising waning gibbous Moon light the sky over the old barn near home at harvest time, September 19, 2016. The glows from Strathmore and Calgary light the clouds to the west at far left. The Big Dipper shines over the barn, with Capella and the stars of Perseus at right. The Pleiades are rising to the left of the Moon. This is a panorama of 5 segments, with the 20mm lens and Nikon D750. Stitched with ACR.

The image above was from later in the night, just down the road at a favourite and photogenic grand old barn.

Big Dipper and Aurora over Old Barn #1
The Big Dipper and a diffuse aurora over the old barn near home, in southern Alberta, on September 16, 2016. The waning gibbous Moon off camera at right provides the illumination. This is a stack of 4 exposures, averaged, for the ground to smooth noise and one exposure for the sky to keep the stars untrailed. All 13 seconds at f/2.8 with the Sigma 20mm lens, and ISO 1600 with the Nikon D750. Diffraction spikes on stars added with Noel Carboni’s Astronomy Tools actions.

Note the Big Dipper above the barn. A waning and rising Moon like this is great for providing warm illumination.

The time around equinox is usually good for auroras, as the interplanetary and terrestrial magnetic fields line up better to let in the electrons from the Sun. So perhaps we’ll see more Lights, with the Moon now gradually departing the evening sky.

— Alan, September 20, 2016 / © 2016 Alan Dyer / www.amazingsky.com

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Sweep of the Auroral Oval


Arc of the Northern Lights

The aurora has been lighting up our skies a lot in recent nights, in a great sweeping arc across the northern sky.

It’s been a good week or so for Northern Lights, with several nights in a row of fine displays. These images are from one night, taken near home in southern Alberta, on September 2.

The lead image at top shows the display at its best, with the arc of curtains reflected in a nearby pond. The green curtains fade to shades of magenta as they tower into the high atmosphere, as one process of glowing oxygen giving off green light transitions to another emitting red light.

Concentric Arcs of the Auroral Oval
A 180° panorama of the Northern Lights exhibiting classic concentric ars across the north, with an isolated arc to the east at far right. This is a stitch of 10 segments, each 2-second exposures with the 20mm Sigma Art lens at f/1.6 and Nikon D750 at ISO 3200. Stitched with PTGui.
A little later the curtains had changed form, into a more homogenous arc above a set of sharper curtains below that are farthest north. People in northern Alberta or the Northwest Territories would have been seeing these curtains dancing above them.

What we are seeing is the classic curving arc of the auroral oval, the ring of light created by electrons raining down into our atmosphere in roughly an oval sweeping across the continent and centred on the magnetic pole in the Canadian Arctic.

However, at right, you can see a odd detached bit of more southerly aurora, with a dominant red colour.

Isolated Auroral Arc #2 (Sept 2, 2016)
An isolated auroral arc to the east on September 2, 2016, shot from near home during a fine display with active curtains to the north at left. A single 8-second exposure with the 20mm lens at f/1.4 and Nikon D750 at ISO 3200.
This is a closeup, showing the characteristic form of these odd “isolated arcs” — usually featureless, often thin, without much motion, and often red.

Isolated Auroral Arc #4 (Sept 2, 2016)
An isolated auroral arc to the west on September 2, 2016, shot from home during a fine display with active curtains to the north. A single 13-second exposure with the 20mm lens at f/1.4 and Nikon D750 at ISO 3200.
Later, the arc had brightened and expanded to cross the sky. The above view is looking west from home, with the arc now displaying a mix of pink, white and green.

Isolated Auroral Arc #3 (Sept 2, 2016)
An isolated overhead auroral arc on September 2, 2016, shot from home during a fine display with active curtains to the north. The Summer Triangle stars stand out here due to high cloud fuzzing their images. A single 13-second exposure with the 20mm lens at f/1.4 and Nikon D750 at ISO 3200.
Here, we are looking up the isolated arc, with the impression of it being a thin sheet seen at an angle, with the bottom green component being closest and the red top being highest and farthest away.

Isolated Auroral Arc #5 (Sept 2, 2016)
An isolated auroral arc to the southeast on September 2, 2016, shot from home during a fine display with active curtains to the north. This one displays the classic picket fence apperarance, with fingers of green aurora that moved along the band during a time-lapse of the scene. A single 13-second exposure with the 20mm lens at f/1.4 and Nikon D750 at ISO 3200.
This is the view looking southeast to the strange aurora. For a time it broke up and displayed a “picket fence” formation. And it moved!

 

Just what these isolated arcs are is a mystery. They have been called “proton arcs,” under the assumption they are caused by incoming protons, not electrons. But while there are such things as proton arcs and auroras, they are diffuse and invisible to the eye and camera in normal visible light. So these features are not proton arcs. 

Nevertheless, these odd arcs are not like the usual auroral curtains, and likely have a different origin. But just what is still the object of research. Images by amateur astronomers such as these can help in the study.

— Alan, September 7, 2016 / © 2016 Alan Dyer / www.amazingsky.com

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A Night at Moraine Lake


Aurora over Desolation Valley PanoramaWhat a night this was – perfect skies over an iconic location in the Rockies. And an aurora to top it off!

On August 31 I took advantage of a rare clear night in the forecast and headed to Banff and Moraine Lake for a night of shooting. The goal was to shoot a time-lapse and stills of the Milky Way over the lake.

The handy planning app, The Photographer’s Ephemeris, showed me (as below) that the Milky Way and galactic centre (the large circles) would be ideally placed over the end of the lake as astronomical twilight ended at 10:30 p.m. I began the shoot at 10 p.m. as the sky still had some twilight blue in it.

Moraine Lake TPE

I planned to shoot 600 frames for a time-lapse. From those I would extract select frames to create a still image. The result is below.

Milky Way over Moraine Lake
This is looking southwest with the images taken about 11:15 pm on August 31, 2016.The ground is illuminated by a mix of starlight, lights from the Moraine Lake Lodge, and from a display of aurora brightening behind the camera to the north. The starclouds of Scutum and Sagittarius are just above the peaks of the Valley of Ten Peaks. This is a stack of 16 images for the ground, mean combined to smooth noise, and one exposure for the sky, untracked, all 15 seconds at f/2 with the Sigma 20mm Art lens and Nikon D750 at ISO 6400. The frames are part of a 450-frame time-lapse.

As the caption explains, the still is a composite of one exposure for the sky and 16 in succession for the ground, averaged together in a technique to smooth noise. The camera wasn’t tracking the sky, so stacking sky images isn’t feasible, as much as I might like to have the lower noise there, too. (There are programs that attempt to align and stack the moving sky but I’ve never found they work well.)

About midnight, the Valley of Ten Peaks around the lake began to light up. An aurora was getting active in the opposite direction, to the north. With 450 frames shot, I stopped the Milky Way time-lapse and turned the camera the other way. (I was lazy and hadn’t hefted a second camera and tripod up the steep hill to the viewpoint.)

The lead-image panorama is the first result, showing the sweeping arc of Northern Lights over Desolation Valley.

Aurora over Desolation Valley #2
The Northern Lights in a fine Level 4 to 5 display over Desolation Valley at Moraine Lake, Banff National Park, on the night of August 31/Sept 1. This is one frame from a 450-frame time-lapse with the aurora at its best. This is a 2-second exposure at f/2 with the Sigma 20mm Art lens and Nikon D750 at ISO 5000.

Still images shot, I began a time-lapse of the Lights, grabbing another 450 frames, this time using just 2-second exposures at f/1.6 for a rapid cadence time-lapse to help freeze the motion of the curtains.

The final movies and stills are in a music video here:

 

I ended the night with a parting shot of the Pleiades and the winter stars rising behind the Tower of Babel formation. I last photographed that scene with those same stars in the 1980s using 6×7 film.

Aurora and Winter Stars Rising over Tower of Babel
The early winter stars rising behind the Tower of Babel formation at Moraine Lake, Banff National Park, with a bright aurora to the north at left. Visible are the Pleiades at centre, and Capella and the stars of Auriga at left. Just above the mountain are the Hyades and Taurus rising. At top are the stars of Perseus. Aries is just above the peak of Babel. The aurora in part lights the landscape green. This is a stack of 16 images for the ground, mean combined to smooth noise, and 1 image for the sky, untracked, all for 15 seconds at f/2.2 with the Sigma 20mm Art lens, and Nikon D750 at ISO 3200. All with LENR turned on.

In a summer of clouds and storms, this was a night to make up for it.

— Alan, September 4, 2016 / © 2016 Alan Dyer / www.amazingsky.com

Member of The World at Night photo group

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