Glaciers and Galaxies
The long weekend weather forecast is stunning, with a new moon and clear skies from Lake Louise to Jasper. The plan is to hike up to Wilcox Pass, across from the Columbia Icefields, and photograph the stunning glaciated peaks (Athabasca and Andromeda) with the Southern Milky Way above. In addition to the fantastic hiking, skiing and mountaineering that Jasper National Park has to offer, it has also been designated a Dark Sky Preserve.
I’ve photographed the night sky above the Athabasca Glacier before, from the parking lot at the interpretive centre, but there are quite a few lights there, on the building itself, from traffic driving up and down the highway, and from RVs parked in the lot, which is one of the main motivations to shoot from Wilcox Pass. The other motivation is to get the better perspective of icefield peaks by gaining the 350m or so to the pass. The night photo gear includes a sturdy tripod, a heavy three-axis tripod head, an AstroTrac equatorial tracker, a battery to power it, another tripod head, and the camera and lenses. Plus warm clothes, a sleeping bag and some food and water. The plan is to haul all that stuff up to the pass, wait for night, shoot for a few hours, and then either walk back in the dark or hunker down and wait until dawn.
After a lazy morning breakfast and then some hiking around tourist spots I pack up and head up the trail to Wilcox pass around 3:00 and wander over to the rounded, rocky edge that offers a clear view across the valley to the Columbia Icefields and the Athabasca Glacier. I’m looking for a good, flat area to setup the camera as well as a sheltered site to spend the night, since I really doubt that I’m going to walk three hours back down to the car, in the dark.
Wilcox Pass is a popular hike, and there are lots of folks up here enjoying the stunning day. Meet some nice folks from the Czech Republic who are on a Rockies tour and we chat a while – I love meeting people who are having the time of their lives in my backyard mountains! By 5:30 most folks have wandered back to their cars, and the pass becomes beautifully quiet. There are still several hours to go before sunset, the sun is out and the sky is clear. The warmth, peacefulness and beauty of the place is magical!
7:00 now and what a sweet luxury, to have a few hours with nothing to do. After the last several years of constantly struggling to find time to do all the things that “need” doing and never being able to do anything properly because there is never enough time, here I finally am with time on my hands. Hours of glorious time! Watching the sun slowly set behind Mt Kitchener and the shadows grow long across Athabasca is glorious, and I set up the camera to take a time-lapse series of exposures. Frames every two minutes should be good, staring about 7:30 until full dark at 9:30 or so.
As the sun goes down behind the peaks, it cools off quickly and I need to add layers of clothing. First the toque, then the long underwear, and the extra fleece shirt as the last rays of sun leaves the pass until tomorrow.
The edge of Wilcox pass, where it overlooks the valley, is rolling terrain, covered in either heather or broken rocks. The best location to setup the camera is out in the open and quite windy, which is going to be cold, plus I’m also concerned about camera shake from the wind. Strolling around trying to find a sheltered spot… Hmmm. Meanwhile the sky remains clear and stunning – an amazing evening!
Shooting the time-lapse of the setting sun goes by surprisingly quickly. The exposure needs to be slowly adjusted, from frame to frame, after the sun goes down and the sky darkens, and that keeps me peacefully occupied. At first I’m increasing the exposure 1/3 stop per frame, but after sunset it takes 1/2 a stop, and then a full stop more exposure, every two minutes. The first star is visible at 20:56, straight up, which is later identified as Vega. Also decrease the frame rate slightly after sunset as the light conditions are changing more slowly. At 21:00 the puffy winter jacket comes out… Its going to be a chilly night.
21:30 now and the time lapse continues. Cygnus is becoming visible, next to first-star Vega. There’s a bright star visible in the south, above the Athabasca glacier, later identified as Antares. Now, at 21:35 I’m shooting frames every 3 minutes, and adjusting the exposure to keep the brightness roughly constant.
The sleeping bag and thermarest come out and get put into the bivy bag to make a nice ground pad, and that keeps me much warmer when I plop down on it between frames. It is absolute magic lying there, watching the sky darken and the stars come out!
At about 22:00 there is still some sky glow visible in the NE and the Milky Way is just becoming visible. A couple meteors have zipped by already, and some funny clouds keep forming, directly overhead, right in Cygnus, but they are small and dissipate quickly. Hopefully they don’t keep doing that all night.
Finished shooting the time-lapse series and I move the tripod to the open location with the better valley view and setup the star-tracker. Meanwhile, the clouds in the north have fattened up and I need to wait until there’s a brief moment when the north star, Polaris, is visible so that the star tracker can be aligned. Some clouds have also appeared over the icefield, blocking the view of the most southerly part of the Milky Way. Even though there is no moon, and it’s fully dark now, the sky seems very bright tonight, and I am able to walk around just by starlight, and the same exposures as last night (2 minutes, f2.8 at ISO 800) look brighter. Hmmm, maybe it’s the total lack of light pollution fooling my mind.
The night settles into a 2-minute rhythm: open the camera, set the timer, lie down and gaze at the sky, or write notes, or identify stars and constellations using the fantastic Star Walk app on the phone, get up when timer rings, move camera to next frame (or repeat the frame because of airplanes flying through the frame, or clouds forming). Check the image for focus once in a while – the camera is on manual exposure and manual focus, and it’s easy to bump a dial while fumbling with it in the dark. Don’t forget to set the timer for the next frame. Repeat. If you fall asleep, the timer will wake you. If you hear a strange noise, that will wake you too! Nothing freaks me out, here by myself in the dark, like an unusual noise. Boo! Every once in a while a sound like thunder rumbles across the valley, but it’s serac fall off the icefields, not storms.
The thick, spotty, northern clouds persist until around 1:30, which is quite annoying. On and off they are clear enough to image Cygnus, and occasionally there are moments of stellar clarity in the sky, but then the clouds form again. Occasional flashes of light on the western horizon, but I’m not too concerned about storms tonight as the clouds that do form overhead dissipate again. Now it’s nearly 2:00, I’m getting very sleepy but the sky seems to be clearing. Must keep shooting when it’s good! And it’s fairly warm and calm – very comfortable in the puffy jacket lying on the bivy bag.
Glaciers, and mountains in general, have always filled me with a feeling of profound humility. The vast masses of ice and rock, completely indifferent to our existence, have existed for time beyond human reckoning, and the planetary forces that direct the movement of glaciers and the building and erosion of mountains are completely beyond the scale of mere humans. And yes, with care and respect, we humans can travel through these mountains, visit their summits, and return safely. And yet the vastness of mountains and glaciers are just a minutely thin skin on our planet Earth, which is a tiny, fragile blue dot compared to our Sun and the rest of our solar system in the cold, empty blackness of space. And our Sun is just one average star out of 100-400 billion in our galaxy, the Milky Way. To put 1 out of 200,000,000,000 in perspective, it is roughly one second out of 6400 years. Or 5 litres out of a cubic kilometer of water. And there are roughly that many galaxies in the universe. Gives a humbling perspective to our petty concerns as humans on this fragile, beautiful little ball, a perspective that was perhaps best voiced by Carl Sagan in his powerful and poetic Pale Blue Dot.
After maybe another hour of shooting, I can’t keep my eyes open anymore and it’s time to tuck into the bag and get a few hours of sleep. The Earth rotates me around and the Universe rolls over my face…
After a brief few hours sleep, wondering if I’ll be awoken by a squirrel chewing on my nose, the sky brightens and I groggily get out my cozy bag to grab a quick self-portrait before packing up and heading off for a little walk up towards Mt. Wilcox. The morning light is just stunning and I’m in a completely relaxed and peaceful mood (or is it just half asleep?), all alone in one of the most beautiful locations in the Canadian Rockies.
Decide to head up Wilcox, since I’m here, and meet up with two guys who are already on the way down after a very early start. Get most of the way up but decide to turn back since the rock is very loose, it’s quite steep, and I don’t have a helmet. And after yesterday’s mellowness and the overwhelming feeling of smallness after last nights star gazing, I’m just not in the mood for the adrenaline of steep, loose rock.
There’s usually a herd of bighorn sheep hanging out at Wilcox Pass, but there’s been no sign of them yesterday or today. The only wildlife I see is a raven playing in the morning breeze and group of ptarmigans pecking at the heather in the rocky meadows. A beautiful, relaxed morning, as far away from stress as I can imagine.
Left: low-angle morning light brings out the meanders of the creek in the morraine below Snowdome. Below: beautiful light looking down on Wilcox pass and across at Mts. Athabasca and Andromeda, Athabasca Glacier and Snowdome and Kitchner from the ridge of Mt. Wilcox.
A properly adjusted monitor is key to viewing photographs accurately. Adjusting the Contrast and Brightness of your monitor should allow you just barely distinguish between the different shades of gray on the following strip.
Putting together dozens of frames
It takes two nights to capture the frames that go into this image, and as many more days to process them, adjusting colour, brightness and contrast, stitching the sky frames together and then overlaying the ground frames. The sky frames and ground frames are shot separately because the sky frames are tracked, following the rotation of the Earth, while the ground frames are stationary. All frames were shot with a 28mm, f1.8 lens, stopped down to f2.8 to increase sharpness and reduce aberrations, and were two-minute exposures at ISO 800.
There are many web pages explaining the processing of astronomical images, and only basic processing including contrast, colour, brightness and noise reductions, were applied to these frames, all in Adobe Lightroom.
The individual frames are then exported as TIFF files to be stitched together, using PTGui, into the complete image. The individual frames overlap each other by at least 1/3, and it’s just a matter of aligning a few stars in one frame with the same stars in the neighbouring frames… tedious work for sure. More difficult was getting the colours consistent from one frame to the next, as the sky-glow was changing subtly and the same part of sky would be in a different position, due the constant rotation of the Earth, from one row of images to the next.
The final image is composed of 26 frames for the sky and another 6 for the ground and totals over 100 megapixels.
Exploring the image
Browsing the full-sized image and looking for the visible Messier and NGC objects reveals that these two-minute exposures with the little 28mm lens have captured an amazing number of deep-sky objects.
Cygnus, The Swan
High in the sky, almost vertical in late summer, Cygnus the Swan, also known as the Northern Cross, is a very prominent constellation, flying down the centre of the Milky Way towards the south.
NGC6940 is a open cluster just off the right wing of Cygnus, while the enormous North America nebula, NGC 7000, is just north of Cygnus. NGC 7000 is a stellar nursery, and recent infrared images, which peer through the galactic dust, taken the Spitzer Space Telescope have revealed more than 2000 new candidate stars.
Barely visible is the Veil Nebula, a thin wisp of glowing gas that is the remnant of a supernova that exploded 5000 – 10000 years ago. The full nebula covers an area of almost 3 degrees of sky, about 6 times the diameter of the full moon. What is visible in this image is just the brighter, eastern side of the explosive remnant. It is an amazing structure, and the Hubble telescope has zoomed into parts of it.
In the southern part of the galaxy the stars are obscured by dark galactic dust clouds. When these clouds are illuminated they can form reflection nebula, and when the gas (usually hydrogen) is heated by nearby stars to the point where it is ionized, the clouds form emission nebula, but otherwise they are dark, and block the light of the stars behind them. These resulting dark bands in the Milky Way are quite visible to the naked eye under very dark skies and are perhaps the most dramatic feature of our galaxy, spanning almost 1/3 of its length. The large swath of dark gas visible here is known as the great rift.
Difficult to find, nearly impossible without a star map, are several globular clusters, which in this wide-angle image appear as fuzzy stars but can be resolved by large telescopes into dazzling gems of 100,000 or more stars.
At 10 billion to 13 billion years old, they are truly ancient, nearly as old as the Universe itself. There are roughly 150 known globular clusters orbiting in the halo of our Milky Way, with more yet undiscovered. Other galaxies have swarms of these objects in scattered orbits around their centres, as spectacularly shown in this image of the Sombrero Galaxy.
The formation of these clusters is still a mystery. While they only appear as fuzzy, unimpressive blobs at this very low magnification, learning what they are and what you are looking at is mind-boggling!
Star forming nebula and star clusters in Sagittarius
About 6000 light years away, Messier 17 (bottom centre) is one of our galaxy’s most luminous and massive hydrogen-emission regions. Ground and space telescope data were used to create this amazing image of M17.
Messier 16, also known as the Eagle Nebula, in the upper right, is another rich star-forming nebula, glowing from ionized hydrogen. Deep inside M16 are the enormous towers of gas known as the Pillars of Creation, perhaps the most famous image made by the Hubble Space Telescope
M18, M25, and M24 are open (loose) star clusters of varying sizes, from around 30 for M18 to 1000s for M24. Star clusters are formed from the gravitational collapse of vast dust clouds. During this collapse the the clouds, mostly hydrogen, can glow red from being ionized by the energy being spewed out by hot, young stars. As the gas clouds dissipate, due to high-speed stellar wind emanating from the new stars, leaving behind the newly-hatched cluster of stars. NGC 3603 is a fantastic example of these stellar life-cycle processes at work.
M24, known as the Sagittarius Star Cloud, is not a true star cluster, but a superposition of dense star fields along our line of sight.
M23 is the open cluster at top-right, while M20, the Trifid nebula, is a stunning mass of gas clouds, glowing red from hydrogen emission as well as reflecting the blue light of bright young stars, just disappearing behind horizon at bottom-left. All of these objects are much better viewed from further south, where they can be seen much higher in the sky, and therefore though much less atmosphere.
Aquila, the Eagle
M27, the “Dumbbell Nebula” is a blue/green cloud of gas ejected by the star at its centre, several thousand years ago. The central star is extremely hot, and the gas is mostly oxygen, doubly ionized. Circular nebulae like this one are formed by stellar explosions that blow off vast quantities of gas and are called Planetary Nebula, because they resemble planets in small telescopes. There are many great photographs of M27, this is one of the nicer ones in my opinion.
Nearby is Messier 71, a relatively small and unusual globular cluster. Very old, at around 10 billion years, but that is a relatively young age for globular clusters. It is also a fairly sparse cluster, without the typical very dense core.
Below Aquila is M11, an open star cluster. At around 6000 light-years, it is relatively far away and contains about 2900 stars. Estimated age is about 250 million years, much younger than globular clusters.
Throughout the sky there appear loops and swirls and occasionally squares (!) of stars. I don’t know if these patterns are true stellar groups – meaning that the stars formed together, like a cluster – or if they are related to each other some other way. Most likely they are simply asterisms, stars that appear in a group only due to our perspective.
This annotated image shows the location of the various objects that I’ve identified, and you can be sure that I’ve missed a bunch of them. It’s a matter of spending the time comparing the full resolution image to a good star chart, identifying constellations, and star-hopping until you spot a fuzzy object that aligns with what’s on the star chart.
Click to zoom the annotated image
All of the Messier objects (M-numbered) were cataloged between 1758 and 1782 by Charles Messier, a French astronomer whose main interest was comet hunting. The Messier Catalog, containing 110 deep-sky objects, was originally intended as a list of “not comets”, since the appearance of these objects (fuzzy blobs) through the telescopes of the day were very similar to comets. As telescopes improved, Messier’s collection of objects was revealed to be a collection of some of the most fascinating and beautiful objects in the cosmos, and the investigation into the true nature of these objects has led humanity to a vastly better understanding of the Universe and our place within it.
In 1888, about 100 years after the publication of Messier’s catalog, the New General Catalog was published, and contains 7840 objects. After that, there were two supplementary Index Catalogs published, in 1895 and 1908, containing an extra 5386 objects. The sky is a busy place!
We have been mapped the night sky for centuries – the classic work for almost 2000 years is the Almagest, written by Ptolemy in the 2nd century AD and derived from the work of Hipparchus in the 1st century BC. A slightly more modern reference is the excellent Stellarium Project, an open source application with a very detailed object database and fantastic visuals.
The mapping of the Universe is a project of nearly infinite scope, and continues today with the Sloan Digital Sky Survey, which has imaged over 50 million galaxies alone, and has produced the largest colour image of the sky ever made: one million megapixels.
Another fascinating project is the CANDLES Survey being performed by the Hubble Space Telescope. The galaxies that CANDLES is surveying are far, far away, in both space and time, and their visible-light has been stretched into longer (infrared) wavelengths by the expansion of the universe, a process called redshift. They are so far away that they are now barely detectable in visible light, and an infrared camera (WFC3) was installed on the Hubble in 2009 to image such distant galaxies.
Finally, here’s a 1/4 resolution strip through the middle of this image, covering over 100 degrees of sky. Climbers may recognize the aptly named Skyladder route on Mt. Andromeda, next to the icefall on the Athabasca glacier.
To clear, dark skies and wild places!
©2013 Darren Foltinek