Hello, Austral Autumn Sky


Southern Autumn Sky Panorama (Spherical)

The sky looks very different from down under. This is the entire sky of early evening as autumn begins in the southern hemisphere.

My last post showed Orion and the winter sky disappearing into the west, from home in Alberta.

This post shows that same area of sky (here at top) also setting into the west. But that’s the only area of sky familiar to northern hemisphere stargazers.

Everything below Orion and Sirius is new celestial territory for the northern astronomer. Welcome to the fabulous southern hemisphere sky.

And to the autumn sky – From home it is spring. From here in the southern hemisphere summer is giving way to cool nights of autumn.

Straight up, at centre, is the faint Milky Way area containing the constellations of Puppis and Vela, formerly in the constellation of Argo Navis.

Below, the Milky Way brightens in Carina and Crux, the Southern Cross, where dark lanes divide the Milky Way.

At right, the two patches of light are the Large and Small Magellanic Clouds, satellite galaxies of our Milky Way.

The bright object at left is Jupiter rising over the Tasman Sea.

Southern Autumn Sky Panorama (with Labels)

I shot this 360° panorama on March 31, 2017 from Cape Conran on the Gippsland Coast of Victoria, Australia, at a latitude of 37° South.

I’ve turned the panorama so Orion appears as we’re used to seeing him, head up and feet below. But here in the southern hemisphere the image below despicts what he looks like, as he dives headfirst into the west in the evening twilight.

Orion and Waxing Moon Setting at Cape Conran

The bright object here is the waxing crescent Moon, here in Taurus. Taurus is below Orion, while Sirius (the bright star at top) and the stars of Canis Major are above Orion.

Orion, the Milky Way and Waxing Moon at Cape Conran

This view above takes in more of Canis Major. Note the Pleiades to the right of the Moon.

Visiting the southern hemisphere is a wonderful experience for any stargazer. The sky is disorienting, but filled with new wonders to see and old sights turned quite literally on their heads!

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

 

Farewell Winter Sky


Panorama of the Winter Sky in March

As we celebrate the official arrival of spring in the Northern Hemisphere, we bid adieu to the stars of winter.

This was the scene last night from my backyard, of Orion and the surrounding constellations of the winter sky setting into the southwest in the early evening. Each night they will set sooner and sooner, even as the nights continue to grow shorter and the Sun sets later.

By late April Orion will be gone from our Northern Hemisphere sky — he hangs around until well into May for sites south of the equator.

Panorama of the Winter Sky in March (with Labels)
A horizon-to-zenith panorama of the winter consellations on a March evening as they set into the southwest. Taken from home March 19, 2017. This is a panorama of 5 panels, each with the 20mm Sigma Art lens at f/2, and Nikon D750 at ISO 3200, for 25 seconds each. Stitched with Adobe Camera Raw.

In this version I’ve labeled the main characters in this winter hunting scene – including some of the deep-sky “Messier”  objects like M45, the Pleiades; M44, the Beehive star cluster; and M42, the Orion Nebula.

At the same time this year, we also say goodbye to Venus which has shone so brightly these last few months as an evening star. By this weekend, it will be lost from sight as it passes between Earth and the Sun.

Mercury Rising and Venus Descending (with Labels)
Mercury (left) and Venus (right and bright) shinng low in the evening twilight, on March 19, 2017. Mercury was then 2 weeks before greatest elongation while Venus was a week before inferior conjunction. So Mercury was rising into the evening sky while Venus was rapidly descending. This is a 7-image HDR stack of exposures from 2.5 seconds to 1.6-second at ISO 200 with the Canon 6D and with the Sigma 50mm lens at f/4.

Meanwhile, Mercury is rising into view in the evening twilight, in its best evening showing of the year from northern latitudes. The view below is also from March 19, with Mercury to the left of brighter Venus.

Over the next two weeks, look low in the west for a bright star amid the twilight. Mercury appears farthest from the Sun on April 1, the date of its “greatest elongation.”

Having Mercury in our evening sky is a sure sign of spring.

Leo and the Spring Stars Rising
Leo rising in the east along with the northern hemisphere spring stars. Numerous satellite trails are visible. I didn’t clone them out. This is a vertical panorama of 4 frames, with the 20mm Sigma Art lens at f/2 and 25 seconds at ISO 3200 with the Nikon D750. Stitched with PTGui using Transverse Equirectangular projection.

Another sign of spring is Leo the lion.

While Orion sets in the west, the stars of spring are rising in the east. The panorama above depicts the scene in the eastern sky these nights, as Leo rises below the Big Dipper.

The Big Dipper is at upper left, with its handle pointing down to Arcturus at bottom left. The Bowl of the Dipper points down to the right to Regulus and the stars of Leo.

Above Leo is the star cluster M44, the Beehive, in Cancer. Below Leo at centre is the star cluster Mel 111, the Coma Berenices star cluster near the North Galactic Pole.

Happy Equinox! 

— Alan, March 20, 2017 / © 2017 Alan Dyer / amazingsky.com

 

 

The Ghostly Glow of Gegenschein


Northern Spring Sky Panorama

It takes a dark spring night to see it well, but now lurking near Jupiter is a ghostly sky glow called Gegenschein. 

This diffuse glow lies directly opposite the Sun. It is caused by sunlight reflecting off interplanetary dust particles in the outer solar system. They reflect light more effectively at the anti-Sun point where each dust particle is fully lit by the Sun.

Like the Sun, the Gegenschein moves around the sky along the ecliptic, moving about a degree from west to east from night to night. March and April provide good nights for seeing the Gegenschein as it then lies in an area of sky far from the Milky Way.

Even so, it is very subtle to the unaided eye. Look south at about 1 a.m. local daylight time.

However, this year, in early April the Gegenschein will be more difficult as it will then lie right on top of Jupiter, as that planet reaches its point opposite the Sun on April 7. Jupiter will then be superimposed on the Gegenschein.

The main image at top is a 7-image vertical panorama of the spring sky, from Corvus and Virgo above the horizon, up past Leo, into Ursa Major and the Big Dipper overhead. Spica lies below bright Jupiter, Arcturus in Böotes is at left, while Regulus in Leo is at right. The grouping of stars near centre is the Coma Berenices star cluster.

Orion over the Old Barn

Earlier in the night, I shot the sky’s other main glow – the Milky Way, as the winter portion of the Milky Way around Orion set into the southwest.

But over in the west, at the right edge of the frame, is the Zodiacal Light, caused by the same dust particles that create the Gegenschein, but that are located in the inner solar system between us and the Sun.

The Zodiacal Light is better depicted in images in my previous post from Dinosaur Park

We bid adieu to the winter Milky Way now. As it departs we are left with an evening sky without the Milky Way visible at all. As seen from northern latitudes it lies along the horizon.

But later in spring, late at night, we’ll see the summer Milky Way rising, beginning its seasons of prominence until late autumn.

— Alan, March 19, 2017 / © 2017 Alan Dyer / AmazingSky.com 

 

Toward the Centre of the Galaxy


Toward the Centre of the Galaxy

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.

Starclouds and Stardust – Mosaic of the Galactic Centre
This is a mosaic of 6 segments, each segment being a stack of 4 x 3-minute exposures at f/2.8 with the 135mm Canon L-Series

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.

Centre of the Galaxy Area
This is a stack of 5 x 5 minute exposures with the Borg 77mm f/4 astrograph and filter-modified Canon 5D MkII at ISO 1600, taken from Tibuc Cottage near Coonabarabran, NSW, Australia.

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.

Milky Way Overhead Through Trees
This is a stack of 5 x 6-minute tracked exposures with the 15mm fish-eye lens at f/4 and Canon 5D MKII at ISO 1600. The trees appear to be swirling around the South Celestial Pole at lower right above the Cottage.

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.

– Alan, April 17, 2016 / © 2016 Alan Dyer / www.amazingsky.com

 

Red Rivals in Scorpius


Red Rivals in Scorpius

Mars outshines his rival red star Antares in the heart of the Scorpion.

This was the view last night from my observing site in Australia, of red Mars shining near the red star Antares, whose very name means “rival of Mars.” But as Mars nears its closest approach to Earth next month it is already far brighter than Antares, easily winning the rivalry now.

The view takes in the head of Scorpius, one of the most colourful areas of the night sky when photographed in long exposures. Uniquely, Antares illuminates a nearby dust cloud with its light which is more yellow than red.

Other dust clouds reflect the blue light of hot young stars in this section of the Milky Way. Red nebulas are emitting their own light from glowing hydrogen.

The area around Antares is also streaked with lanes of dark dust that absorb light and at best appear a dull brown.

Mars reaches its closest point to Earth since 2005 on May 30. All through May and June Mars will shine as a brilliant red star near Antares. A telescope will provide the best view of the red planet we’ve had in a decade.

Saturn and Mars in Scorpius
This is a stack of 4 x 3 minute exposures with the 135mm telephoto lens at f/2.8 and filter-modified Canon 5D MkII at ISO 1600, shot April 14, 2016 from Tibuc Cottage, Australia.

While you are in the area aim your telescope a little to the east to catch Saturn, also in the area, though technically over the border in the constellation of Ophiuchus the Serpent Bearer.

In the view above, Saturn is the bright “star” to the left of Mars. Saturn reaches its closest to Earth in early June. Its rings are now wide open and a spectacular picture postcard sight in any telescope.

Scorpius Rising in Moonlight
This is a stack of 2 x 30-second exposures for the sky and ground, both tracked, plus a 30-second exposure through the Kenko Softon A filter to add the star glows to make the constellation pattern stand out. All with the 35mm lens at f/2 and Canon 6D at ISO 1600. Taken from Tibuc Cottage, Australia.

This final view shows Mars and Saturn rising with Scorpius in the moonlight from two nights ago. From my current latitude of 32° south, Scorpius comes up on his side.

— Alan, April 15, 2016 / © 2016 Alan Dyer  / www.amazingsky.com

Under the Southern Cross


Southern Milky Way Over OzSky Star Party

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.

Star Trails over the OzSky Star Party
Circumpolar star trails over the OzSky star party near Coonabarabran, NSW, Australia, on April 3, 2016. This is a stack of 49 frames, each 45 seconds at f/2.8 with the 15mm fish-eye lens on the Canon 6D at ISO 4000. The ground comes from three frames in the sequence. Stacked with Advanced Stacker Plus actions using Streaks mode.

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.

Southern Milky Way from Alpha Cen to False Cross
The deep south Milky Way from Alpha and Beta Centauri (at left) to the False Cross in Vela and Carina (at right). This is a stack of 5 x 4 minute exposures at f/2.8 with the 35mm Canon L-series lens and filter-modified Canon 5D MkII at ISO 1000, with an additional similar exposure layered in taken through the Kenko Softon A filter to provide the star glows. Tracked on the iOptron Sky Tracker. 

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.

Mosaic of Crux, the Southern Cross
A 3-panel mosaic of the Southern Cross, Crux, shot April 5, 2016 from Tibuc Cottage, Coonabarabran, NSW, Australia. This is a moasic of 3 panels, each a stack of 4 x 4-minute exposures with the Borg 77mm f/4 astrograph and filter-modified Canon 5D MkII at ISO 1600. Stacked and stitched in Photoshop.

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.

The Southern Milky Way and Magellanic Clouds
The deep southern Milky Way arching across the sky, from Puppis and Vela at upper right, to Centaurus at lower left. The two Magellanic Clouds are at lower centre, with the Large Cloud at top. This is a stack of 5 x 1.5-minute exposures, all tracked on the iOptron Sky Tracker, at f/2.8 with the 15mm fish-eye lens, and Canon 5D MkII at ISO 3200. The ground comes from just one of the tracked exposures to minimize blurring. Taken from the Tibuc Gardens Cottage near Coonabarabran, NSW, Australia on March 30, 2016.

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.

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

 

A Panorama of the Spring and Winter Sky


Winter and Spring Sky Panorama

I present a sweeping panorama of the winter and spring stars on a February night. 

The lead image is a panorama I shot last Saturday, February 27 that takes in about 200° of sky from northeast to west, and nearly to the zenith. It encompasses most of the northern spring and winter stars and constellations.

I’ve added the labels to help you pick out the celestial highlights. The winter sky, containing Orion as the central constellation, is at right setting into the west. This area of sky contains a rich collection of bright stars and identifiable constellations.

The left side of the sky contains the spring constellations, now coming into view in the east. Note how that area of sky is sparsely populated by bright stars. You can see the Big Dipper, Regulus in Leo, and Arcturus rising at lower left.

The reason for the difference is the Milky Way – you can see it at right arcing up from the southern horizon passing by Orion and through Gemini, Taurus and Auriga. In that direction we are looking into the outlying spirals arms of our galaxy, toward rich areas of star formation.

To the east, at left, we are looking at right angles out of the plane of our spiral galaxy, toward the galactic North Pole, here just left of Leo. In that direction there are very few bright stars between us and the starless depths of intergalactic space. The spring sky is rather blank compared to the rich winter sky.

But you can see Jupiter, the brightest object in view here, and now prominent in the evening sky.

Note one other subtle glow just above Jupiter. That diffuse glow is the Gegenschein, caused by sunlight reflecting off interplanetary dust opposite the Sun in our solar system and in the plane of the ecliptic.

Jupiter is just east (left) of the Gegenschein here, as Jupiter was then just over a week before its date of opposition, March 8. By then the Gegenschein will have moved to superimpose right over Jupiter, as both then lie opposite the Sun.

Winter and Spring Sky Panorama

I shot this scene from home on February 27, 2016, using the new iOptron iPano motorized “gigapan” unit, which I programmed to move and shoot 36 exposures with the Canon 5D MkII and 35mm lens, arranged in 4 rows high with 9 panels wide in each row from east to west. The result is a huge mosaic, 24,000 by 10,000 pixels.

Each exposure was 25 seconds at f/2 and at ISO 3200. The camera was not tracking the sky. I stitched the 36 segments with PTGui using its Spherical Fisheye projection. The image has black margins but I think the circular format is more suggestive of the spherical dome of the sky above and around you. But that’s me, a longtime planetarium show producer.

Next time I will shoot the zenith cap images as well!

— Alan, February 29, 2016 / © 2016 Alan Dyer / www.amazingsky.com