I present a montage of time-lapses illustrating the motion of the sky in the Northern Hemisphere.
Any stargazer should be familiar with how the sky moves, with stars rising in the east and setting in the west.
From the northern hemisphere, when we look north we see the sky rotating counter-clockwise around the North Celestial Pole, near Polaris. As you’ll see in the video, even Polaris moves, though not much over the night. The stars that never set, but just move across the northern horizon, are the circumpolar stars.
When we look south we see the seasonal constellations, the ones that rise and set, and change over the seasons.
I shot the images for these sequences from southern Arizona, in early December 2015.
So the night starts with the summer stars setting in the west and the autumn stars dominating the sky. But then Orion and the winter stars rise and march across the sky over the night, setting before dawn, as the spring stars rise.
The south-looking movie is a dusk-to-dawn sequence. Note the Zodiacal Light in the west at right in the early evening, then reappearing in the east at left before dawn brightens the sky, and as Venus and the Moon rises.
Also note the moving bands of red and green airglow, a natural phenomenon of the upper atmosphere.
I posted a matching set of moviesin my previous blog post, shot from the Southern Hemisphere. But here’s the link to the movie.
Both sets of movies were shot from nearly identical latitudes – about 31°, but 31° N for Portal, Arizona and 31° S for Coonabarabran, Australia.
As such the Celestial Poles appear at equal altitudes above the horizon. And the angles that the stars rise and set at in relation to the horizon are the same.
But the direction they move is opposite. When looking 180° away from the Pole, the seasonal stars move from left to right in the Northern Hemisphere, but from right to left in the Southern Hemisphere.
Visitors from one hemisphere to the other are bound to get turned around!
The nights were short and never fully dark, but early June provided a run of clear nights in the Rockies to enjoy Mars and the Milky Way.
Weather prospects looked good for a run of five nights last week so I took advantage of the opportunity to shoot nightscapes from Banff and, as shown here, in Yoho National Park across the Continental Divide in B.C.
The lead image above is a sweeping panorama at Emerald Lake, one of the jewels of the Rockies. Though taken at 1:30 a.m., the sky still isn’t dark, but has a glow to the north that lasts all night near summer solstice. Even so, the sky was dark enough to reveal the Milky Way arching across the sky.
The mountain at centre is Mt. Burgess, home of the famous Burgess Shale Fossils, an incredible collection of fossilized creatures from the Cambrian explosion.
The image is a panoramic stitch of 24 segments but cropped in quite a bit from the original, and all shot with an iPano motorized panning unit. Each exposure was 30 seconds at f/2.2 with the Sigma 24mm lens and Nikon D750 at ISO 4000. One short exposure of the lodge was blended in to reduce its light glare. The original, stitched with PTGui software, is 15,000 x 9,000 pixels.
The view above, a single frame image, shows the view to the south as the Milky Way and galactic centre descend toward the horizon over the south end of the lake. Lights from the Lodge illuminate the trees.
The next night (above) I was at the same spot to shoot Mars in the deepening twilight, and reflected in the calm waters of Emerald Lake, with Cathedral Peak at left.
Another multi-frame panorama, this time sweeping up from the horizon, captures Cassiopeia (the “W”) and the rising autumn constellations reflected in the lake waters.
Vega is at top, Deneb below it, while the stars of Perseus and Pegasus are just rising.
It was a magical two nights in Yoho, a name that means “wonderful!” Both by day and by night.
How many sources of skyglow can you pick out here?
There are at least five:
• the Milky Way (at left),
• green airglow (below the Milky Way),
• all too prevalent light pollution (especially reflected off the clouds coming in from the west at right),
• lingering blue twilight across the north (at left and right), common in May and June from my northern latitude,
• and even a touch of aurora right at the northern horizon at far left.
In this scene from May 28, the Milky Way arches over an abandoned pioneer farmstead from the 1930s and 40s near my home in southern Alberta.
Mars (very bright and in some clouds) and Saturn shine at lower centre, while Jupiter is the bright object in clouds at right just above the old house.
Arcturus is the brightest star here at upper right of centre, made more obvious here by shining through the clouds. The Big Dipper, distorted by the map projection used in the this panorama, is at upper right.
Technical: This is a 360° horizon to zenith panorama taken with the iPano motorized panning unit, using the 24mm lens at f/2.8 and Nikon D750 at ISO 6400, for a stitch of 28 panels, in 4 tiers of 7 segments each. Stitched with PTGui. South is at centre, north to either end. The original is 25,700 x 7,700 pixels.
Just after I shot the panorama I captured the International Space Station passing directly overhead in one of several passes this night.
At this time of year the ISS is lit all night by the Sun that never sets for the astronauts. We see the ISS cross the sky not once but several times in a night at 90-minute intervals.
While the sky near solstice is never dark at my latitude, it does have its compensations and attractions.
The sky and sea present an ever-changing panorama of light and colour from the view point of an Australian lighthouse.
Last week I spent a wonderful four nights at the Smoky Cape Lighthouse, in Hat Head National Park, on the Mid-North Coast of New South Wales. I was after panoramas of seascapes and cloudscapes, and the skies didn’t disappoint.
At sunset, as below, the sky to the east glowed with twilight colours, with the bright clouds providing a beautiful contrast against the darkening sky. The kangaroo at far right was an added bonus as he hopped into frame just at the right time.
At sunrise, the Sun came up over the ocean to the east, providing a stunning scene to begin the day.
The Smoky Cape Lighthouse was lit up for the first time in 1891. It was staffed for decades by three keepers and their families who lived in the cottages visible in the panoramas above. They tended to the kerosene lamps, to cleaning the lenses, and to winding the weight-driven clockwork mechanism that needed resetting every two hours to keep the reflector and lens assembly turning. By day, they would draw the curtains across to keep the Sun from heating up the optics.
The huge optical assembly uses a set of nine lenses, each a massive fresnel lens, to shot focused beams out to sea. The optics produce a trio of beams, in three sets.
Each night you could see the nine beams sweeping across the sky and out to sea, producing a series of three quick flashes followed by a pause, then another three flashes, the characteristic pattern of the Smoky Bay Light. Each lighthouse has its own flashing pattern.
The lead photo, repeated above, shows the beams in the twilight, with the stars of the Southern Cross as a backdrop. Three beams are aimed toward the camera while the other two sets of beam trios are shooting away out to sea.
The image below shows the beam trio shining out over the water toward one of the dangerous rocks off shore.
The Lighthouse was converted to electricity in 1962, when staff was reduced. Then in the 1980s all lighthouses were automated and staff were no longer needed.
While we might romanticize the life of a lighthouse keeper, it was a lonely and hard life. Keepers were usually married, perhaps with children. While that may have lessened the isolation, it was still a difficult life for all.
Today, some of the cottages have been converted into rentable rooms. I stayed in the former house of the main light keeper, filled with memorabilia from the glory days of staffed lighthouses.
The image above takes in the Southern Cross over the moonlit beach in the dawn twilight.
The last image below is my final astrophoto taken on my current trip to Australia, a 360° panorama of the Milky Way and Zodiacal Light from the back garden of the Lighthouse overlooking the beach at Hat Head National Park.
It’s been a superb trip, with over half a terabyte of images shots and processed! The last few blogs have featured some of the best, but many more are on the drives for future posts.
From southern latitudes the most amazing region of the sky shines overhead late on austral autumn nights.
There is no more spectacular part of the Milky Way than the regions around its galactic centre. Or at least in the direction of the galaxy’s core.
We can’t see the actual centre of the Galaxy, at least not with the cameras and telescopes at the disposal of amateur photographers such as myself.
It takes large observatory telescopes equipped with infrared cameras to see the stars orbiting the actual centre of the Milky Way. Doing so over many years reveals stars whipping around an invisible object with an estimated 4 million solar masses packed into the volume no larger than the solar system. It’s a black hole.
By comparison, looking in that direction with our eyes and everyday cameras, we see a mass of stars in glowing clouds intersected by lanes of dark interstellar dust.
The top image shows a wide view of the Milky Way toward the galactic centre, taking in most of Sagittarius and Scorpius and their incredible array of nebulas, star clusters and rivers of dark dust, all located in the dense spiral arms between us and the galactic core.
Zooming into that scene reveals a panoramic close-up of the Milky Way around the galactic centre, from the Eagle Nebula in Serpens, at left, to the Cat’s Paw Nebula in Scorpius, at right.
This is the richest hunting ground for stargazers looking for deep-sky wonders. It’s all here, with field after field of telescopic and binocular sights in an area of sky just a few binocular fields wide.
The actual galactic core area is just right of the centre of the frame, above the bright Sagittarius StarCloud.
Zooming in again shows just that region of sky in an even closer view. The contrast between the bright star fields at left and the dark intervening dust at right is striking even in binoculars – perhaps especially in binoculars.
The visual impression is of looking into dark canyons of space plunging off bright plateaus of stars.
In fact, it is just the opposite. The dark areas are created by dust much closer to us, hiding more distant stars. It is where the stars are most abundant, in the dust-free starclouds, that we see farthest into the galaxy.
In the image above the galactic centre is at right, just above the small diffuse red nebula. In that direction, some 28,000 light years away, lurks the Milky Way’s monster black hole.
To conclude my tour of the galactic centre, I back out all the way to see the entire sky and the Milky Way stretching from horizon to horizon, with the galactic centre nearly overhead in this view from 3 a.m. earlier this week.
Only from a latitude of about 30° South can you get this impressive view, what I consider one of the top “bucket-list” sights the sky has to offer.
Last week, northerners marvelled at the splendours of the southern hemisphere sky from a dark site in Australia.
I’ve attended the OzSky Sky Safari several times and have always come away with memories of fantastic views of deep-sky wonders visible only from the southern hemisphere.
This year was no exception, as skies stayed mostly clear for the seven nights of the annual star party near Coonabarabran, New South Wales.
About 35 people from the U.S., Canada and the U.K. attended, to take in views through large telescopes supplied by the Australian branch of the Texas-based Three Rivers Foundation. The telescopes come with the best accessory of all: knowledgeable Aussies who know the southern sky and are delighted to present its splendours to us visiting sky tourists.
Here are a few of the night scenes from last week.
The lead image above shows a 360° panorama of the observing field and sky from early in the evening, as Orion sets in the west to the right, while Scorpius rises in the east to the left. The Large Magellanic Cloud is at centre, while the Southern Cross shines to the upper left in the Milky Way.
This panorama, presented here looking south in a fish-eye scene, is from later in the night as the galactic core rises in the east. Bright Jupiter and the faint glow of the Gegenschein are visible at top to the north.
Each night observers used the big telescopes to gaze at familiar sights seen better than ever under Australian skies, and new objects never seen before.
The Dark Emu of aboriginal sky lore rises above some of the 3RF telescopes.
Carole Benoit from Calgary looks at the Orion Nebula as an upside-down Orion sets into the west.
John Bambury hunts down an open cluster in the rich southern Milky Way near Carina and Crux.
David Batagol peers at a faint galaxy below the Large Magellanic Cloud, a satellite galaxy to our Milky Way.
The Southern Cross, the iconic constellation of the southern sky, shines high in the south on austral autumn nights.
I’m in one of my favourite places, Australia, in particular at its self-proclaimed “astronomy capital,” Coonabarabran in New South Wales. Down the road from me is the Siding Spring Observatory.
But for 3 weeks I’m using my own telescope gear to observe and photograph the fabulous southern skies.
For part of my time here I’m attending the annual OzSky Star Party, a small and rather exclusive event for observers from around the world who come here to revel in celestial wonders visible only from southern latitudes.
The lead image at top is a 7-panel panorama of the star party in action, on the grounds of the Warrumbungles Mountain Motel, with a dozen or more large and premium telescopes set up for our use.
Overhead is the arch of the southern Milky Way, with the Southern Cross here at its highest about local midnight now in early April at the start of autumn. Below the Milky Way is the Large Magellanic Cloud, a companion galaxy to the Milky Way, itself a superb target for telescopes.
To the far right in the Milky Way is Sirius amid the gum trees, and the stars of Canis Major diving into the west. To the far left are the bright star clouds of Scorpius and Sagittarius rising in the east, bringing the glowing core of our Galaxy high into the austral sky. Bright Mars and Saturn shine in and around Scorpius.
This is a view of the Milky Way everyone should see – it is should be one of the top items on any amateur astronomer’s bucket list.
Here, above, I’ve stacked images from a time-lapse to create a star trail scene with the stars of the southern sky rotating about the blank South Celestial Pole. Again, the Southern Cross is at top.
This view, above, focuses on the Milky Way of the deep south, from Vela to Centaurus, passing through Carina and Crux, with the bright Carina Nebula, the Southern Cross, and the dark Coal Sack front and centre.
Here I zoom into the Southern Cross itself, in a mosaic of 3 panels to cover the smallest constellation using a high-resolution astrograph, a 300mm f/4 lens. The Coal Sack is at lower left while numerous star clusters lie embedded within and around the Cross, including the famous “Jewel Box” at left, next to Beta Cruxis, aka Becrux.
I shot the Crux mosaic from my cottage site at Tibuc Gardens, a superb dark sky site and home to a new cottage built after the devastating bush fires of 2013 which destroyed all the other cottages I had stayed at in previous years.
There’s much more to come, as I rapidly fill up my hard drive with time-lapses and deep-sky images of the southern sky. I already have several blogs worth of images processed or about to be. In the meantime, check my Flickr site for the latest images hot off the hard drive and uploaded as best my Oz internet connectivity allows.