Sailing Toward Orion


Sailing Toward Orion

Not so long ago sailors used the Moon, Jupiter and the stars to chart their course on Earth. All are in this moonlit seascape.

I took this shot on November 27, as we set sail toward Hook Passage in the Whitsunday Islands, Queensland, Australia. The ship is the Solway Lass, a 110-year-old sailing ship that is now the oldest commercial ship plying the waters around Australia. It has been modernized and refitted, and at night runs with engines, not sails. And today, of course, GPS keeps the skipper informed of where the ship is. But before GPS and radio navigation, sailors used the sky to determine where on Earth they were.

Sextant sightings of the Sun and stars could give them their latitude and longitude. One star often used was Canopus, visible at far right in this image. Canopus has long been associated with the sea. It is the brightest star in Carina the Keel, once part of the sprawling constellation Argo Navis, the ship in the Greek legend of Jason and the Argonauts. Today, Canopus is still sighted by robot spacecraft bound for the planets to help them determine their position in the solar system.

Sirius and the stars of Orion (lying on his side here at a latitude of 20° South) appear through the rigging. At upper left is the bright glow of the nearly Full Moon, near the star Aldebaran and the Hyades star cluster.

Before the acceptance in the late 1700s of the chronometer as an accurate time-keeping device, the position of the Moon near bright stars served as an astronomical clock in the sky to provide sailors with local time. Another source of time (more for land-based navigators) was the changing positions of the moons of Jupiter — Jupiter is the bright star-like object at left.

I just finished a superb 6 days of sailing around the Whitsundays and will have 2 or 3 more sea-bound posts from this wonderful area of the world.

– Alan, November 30, 2012 / © 2012 Alan Dyer

 

Tropical Twilight


Oh, to be on the beach in the tropics now that winter’s here at home.

That’s where I was tonight, at the same beach on Magnetic Island, Queensland where I shot last night’s images of cloud shadows. You can see some of the same effect here, as the few darker clouds cast their dark shadows across the twilight. But in the clearer sky tonight, the classic colours of twilight are more pronounced than they were the previous night. The sunset sky goes from deep yellow near the horizon, through pinkish-purple and into deep blue high in the sky. The “twilight purple” is caused by red sunlight still illuminating the high atmosphere.

We see the same colour effects at temperate latitudes. It’s just a lot more pleasant enjoying a sunset on a warm beach in winter.

– Alan, November 22, 2012 / © 2012 Alan Dyer

 

Cloud Shadows on the Beach


I went to the beach to shoot the sunset and saw one of the best examples of cloud shadows I’d ever seen.

These are called “crepuscular rays,” and are shadows cast across the atmosphere by clouds, in this case in the west blocking the light of the setting Sun. However, here I’m shooting east in the direction opposite the sunset, to see the shadows converging on the anti-Sun point.

The effect is really stunning, yet I doubt anyone on the beach paid much attention to it. But then again, that’s the whole point of my AmazingSky blog — to call attention to neat stuff you can see in the sky if you only look up.

The site is Horseshoe Bay on the north end of Magnetic Island, off the coast of Queensland, near Townsville. I’m here for two days enjoying the island life. It has now been one week since the total eclipse of the Sun. Hard to imagine!

– Alan, November 22, 2012 / © 2012 Alan Dyer

 

The Great Australian Eclipse – The Closeup Movie


This is the “director’s cut” movie of the November 14 total eclipse of the Sun in Australia, unabridged and unedited.

I shot this movie of the eclipse through a telescope to provide a frame-filling closeup view of totality. This is the entire eclipse, from just before totality until well after. So it includes both diamond rings: at the onset of totality and as totality ends.

A few seconds into the movie I remove the solar filter which produces a flash of light until the camera readjusts to the new exposure. Then you really see the eclipsed Sun!

We got 1m28s of totality from our viewing site near Lakeland Downs, Queensland. But the movie times out at slightly less, because at several points where you hear a shutter click, I took a still frame which interrupts the movie. You can see some of those still images in earlier blog posts.

My timing was a little off, as I opened up the exposure to reveal more of the outer corona only moments before the end of totality, so the first moment of the final diamond ring is a little overexposed. During totality I was looking with binoculars, and made the mistake of going over and checking on my other wide-angle time-lapse camera. That wasted time needlessly. I should have spent more time attending to the movie camera and taking more stills at various exposures. No eclipse every goes quite as planned. Losing 30 seconds of totality in order to seek out clearer skies did cost me some images and enjoyment time in the umbra. But our experience was far less stressful than those who dodged clouds (or failed to miss the clouds, in some cases) at sites closer to or at the coast.

The original of this movie is in full 1920 x 1080 HD, shot with the Canon 60Da through the 105mm f/5.8 Astro-Physics apo refractor, on an equatorial mount tracking the Sun. I rarely have the luxury of shooting an eclipse through such extravagant gear, as I would never haul that type of hefty gear now on an aircraft to remote sites. But this equipment emigrated to Australia in 2002 for the total eclipse in South Australia and has been here down under ever since. So this is its second Australian eclipse. Mine, too!

– Alan, November 21, 2012 / © 2012 Alan Dyer

 

Southern Milky Way Setting & Zodiacal Light


On the eve of the November 14 total eclipse of the Sun, I was able to shoot the Milky Way setting amid the vertical glow of the evening Zodiacal Light.

This scene looks west toward the sunset point, but was taken well after sunset. The Milky Way and the area of Sagittarius where the centre of the Galaxy lies is just setting. The same area of sky contains a vertical pillar of light, very subtle, called the Zodiacal Light. This is sunlight reflected off dust particles orbiting the inner solar system and deposited by passing comets. The Zodiacal Light is best seen in the evening sky on dark moonless nights in spring, no matter what your hemisphere. But in this case it is November, spring in the southern hemisphere.

At left are the two Magellanic Clouds, satellite galaxies of the Milky Way, and visible at their best only from south of the equator. In this case we are at 16° South latitude.

The site is a lookout on the Mulligan Highway inland from Port Douglas where we made for the day before the eclipse and camped out overnight, along with a parking lot full of fellow eclipse chasers. But the morning still brought worrying clouds in the direction of the Sun, so we moved farther north to the site you see in my earlier Great Australian Eclipse blogs.

– Alan, November 20, 2012 / © 2012 Alan Dyer

 

The Great Australian Eclipse – Stars & Planets in the Darkened Sky


During last week’s total eclipse, Venus was obvious above the Sun well before the shadow descended and the sky darkened. But during totality other stars and planets appeared.

But I suspect few noticed! During an eclipse your eyes are transfixed on the Sun and its corona. And on the other phenomena of light and shadow happening around you. However, I inspected my wide-angle frames and found faint images of Saturn and the stars Spica, Alpha and Beta Centauri, and three stars of the Southern Cross. I’ve labeled them here but you might not be able to pick them out on screen in the reduced resolution that appears in the blog. Similarly, I doubt anyone saw them visually. If you did you were wasting your time looking at the wrong stuff!

– Alan, November 18, 2012 / © 2012 Alan Dyer

 

Endeavour’s Site at Cooktown, Queensland


I began my journey to Australia with a visit to the replica of James Cook’s ship Endeavour in Sydney. I’m ending this part of my trip with a visit to where Cook beached the HMB Endeavour for repairs at what is now Cooktown in far north Queensland. This is where Cook spent the most time in Australia, though not by intention.

In 1770 Cook was sailing north along the Queensland coast, after visiting Tahiti the year before to see the transit of Venus. He inadvertently discovered the Great Barrier Reef. Endeavour ran aground on what is now called Endeavour Reef. The crew was able to repair the ship well enough and save themselves by getting Endeavour to this harbour at what is now Cooktown where the Cook River meets the Coral Sea. There, with the ship beached, they were able to effect more permanent repairs to its damaged hull.

The site is just below this viewpoint at an idyllic harbour. They stayed there for two months in July and August 1770, effecting repairs and sighting, among other curiosities, kangaroos for the first time.

I visited Cooktown yesterday as part of a 4WD trek up the Bloomfield Track north of Cape Tribulation and through the Daintree Rain Forest. At Cooktown its museum, converted from an old convent, contains the original main anchor and one of the large canons from Endeavour, recovered from where the crew tossed them overboard to lighten the ship’s load and gain draft to sail off the reef. They are some of the few pieces of Endeavour that still remain.

– Alan, November 17, 2012 / © 2012 Alan Dyer

The Great Australian Eclipse – The Shadow Movie


This is 6 minutes of pre- and post-eclipse – and the all too short eclipse itself – compressed into 30 seconds. You can see the dark blue shadow of the Moon sweeping across the sky.

The long oval shadow comes in from behind us from the west and comes down to meet the Sun which is rising in the east. That moment when the shadow edge meets the Sun is second contact when totality begins in a diamond ring effect, and the Sun is entirely hidden behind the Moon.

The shadow then moves off to the right. As its left edge hits the Sun, the Sun emerges in another diamond ring and the eclipse is over. All too soon. Even at mid-eclipse the Sun is not centred in the oval shadow because we were not centred in the path of the shadow but instead drive well north of the centreline, to avoid cloud farther south. We saw 1m28s of totality, 30 seconds less than people at the centreline or on the coast. But we had no annoying clouds to worry about.

Also note Venus at upper left. And the hugs and kisses at the end!

– Alan, November 15, 2012 / © Alan Dyer 2012

 

The Great Australian Eclipse – Our Happy Group!


OK, one last eclipse post! Here’s our happy band of Canadian chasers, post-eclipse.

Some were seeing their first eclipse. A few others, myself included, were chalking up eclipse #14. Eclipse virgin or veteran, the experience is always breathtaking and unbelievable. Moments after the eclipse ends you cannot believe you saw what you did – the sight is so unearthly. And you want to see another. The next total eclipse of the Sun is November 3, 2013, in the mid-Atlantic and over central Africa.

– Alan, November 14, 2012 / © 2012 Alan Dyer

 

The Great Australian Eclipse – Second Diamond Ring


This is the sight eclipse chasers hate to see, yet celebrate the most! It is the diamond ring that ends totality.

This was the “third contact” diamond ring when the Sun returned in an explosion of light from behind the edge of the Moon.

Compare this view to my earlier blog, and you’ll see that the second diamond ring at the end of totality did not happen opposite the first diamond ring. That’s because we were well off the centreline of the Moon’s shadow, so from our perspective the Moon travelled across the Sun’s disk slightly off-centre.

From where we ended up in our chase for clear skies, we experienced 1m28s of totality, well under the 2 minutes maximum that others saw near the centreline. But we felt 1m28s of clear skies was better than 2 minutes under partly cloudy skies. Indeed, some on the coast saw the Sun only briefly during totality, or not at all.

Instead, while the last minute move was stressing, once we were set up, we had relaxed assurance we were going to see the whole show!

– Alan, November 14, 2012 / © 2012 Alan Dyer

The Great Australian Eclipse – Outer Corona


For this shot I overexposed the inner corona on purpose to reveal more of the extent of the streamers in the Sun’s outer corona.

The pink at left is the chromosphere layer shining from behind the Moon just before the Moon uncovered the blindingly bright photosphere with a burst of light, the diamond ring.

It takes a lot of specialized processing, far beyond what I’ve done here, and stacking of multiple exposures to reveal the delicacy of structures that you can see with your aided eyes during a total eclipse. There is nothing more astonishing in the sky for its complexity and yet subtleness than the Sun’s corona. It is the main attraction at any total solar eclipse. You have not lived astronomically until you have seen the corona of the Sun with your own eyes.

– Alan, November 14, 2012 / © 2012 Alan Dyer

 

The Great Australian Eclipse – Inner Corona


Taken shortly into totality, this shot shows some of the complex structure of the Sun’s corona, and a cluster of red prominences peaking out from behind the bottom edge of the Moon.

For the November 14, 2012 eclipse I shot two cameras. One, with a wide-angle lens, was automatically taking a frame every second. Three of those frames are in a previous blog. For this shot I used a second camera looking through a 4-inch refractor telescope I keep stored in Australia. It worked great! I seldom get to shoot an eclipse through a telescope, as so many eclipses are in remote locations where carting a telescope and mount are impractical. But for an Oz eclipse (I’ve seen two from Australia now, in 2002 and now in 2012) I get to use my Oz gear.

Because the Sun is nearing solar maximum its corona appeared evenly distributed around the Sun, with streamers reaching out in all directions. At solar minima eclipses the corona extends just east-west with little over the poles.

This image, like the other closeups I’m posting, are still frames shot while the camera was taking an HD movie. Firing the shutter while the movie is recording interrupts the movie but records a full-resolution still frame, a very nice way to get two forms of media with one camera.

– Alan, November 14, 2012 / © 2012 Alan Dyer

 

The Great Australian Eclipse – Diamond Ring #1


The last bit of the Sun shines from behind the ragged edge of the Moon as the total eclipse begins in Australia.

This is “second contact,” and the first diamond ring effect that heralds the start of totality. The Moon (the dark disk) is just about to completely cover the Sun. You can see the pink chromosphere layer of the Sun’s surface and a flame-like prominence at 4 o’clock position. The Sun’s atmosphere, the corona, is just beginning to show.

I took this November 14, 2012 from a site near Lakeland Downs, Queensland, Australia. While we did look through some thin cirrus clouds, they didn’t hamper viewing at all, and were not the concern that the thicker clouds were at other sites, especially at the beaches.

– Alan, November 14, 2012 / © 2012 Alan Dyer

The Great Australian Eclipse – Success!


It wouldn’t be an eclipse without a chase. But in the end we had a nearly perfect and cloudless view of the entire eclipse — the Great Australian Eclipse. We were ecstatic!

This collage of wide-angle shots shows the motion of the Moon’s conical shadow. At top, you can see the bottom edge of the shadow just touching the Sun. This was second contact and the diamond ring that begins totality. The middle frame was taken near mid-eclipse and shows the bright horizon beyond the Moon’s shadow. However, the Sun is not centred on the shadow because we ended up well north of the centreline, sacrificing as much as 30+ seconds of totality to get assured clear skies. The bottom frame was taken at the end of totality as the first bit of sunlight bursts out from behind the Moon at third contact and the final diamond ring. Notice the Sun sitting at the well-defined left edge of the Moon’s shadow. The shadow moved off to the right.

Why did we end up off-centre? Clouds! The day before, at our 11 am weather briefing meeting, we decided not to stay on the beach but to move inland to one of the sites we selected from the previous day’s reconnaissance. The forecast was not even accurately “predicting” the current conditions at the time, saying the sky should then have been clear. It was raining. We did not trust the predictions that skies would clear by eclipse time on Wednesday morning.

We drove inland on Tuesday afternoon, getting to our choice site at the James Earl Lookout on the Development Road about 4 pm, to avoid driving in the dark and to get there before the parking area filled up. It was a good plan. We arrived to find a few people there but with room for all our cars filled with 20+ Canadians. We staked our ground with tripods, did a little stargazing after dark, then settled in to spend the night in our cars.

At dawn we got everything ready to go, only to see puffs of orographic clouds forming over the hills in the direction of the Sun. I did not like it. So with an hour to go before totality we packed up and moved down onto the plains away from the hills to a site near Lakeland Downs, the site you see here. Apart from some high cirrus clouds, skies were superb.

As it turned out, folks a few miles away at the Lookout did see it, but by the skin of their teeth. Clouds obscured the Sun just before and just after totality. That’s too nerve-wracking for me. And from the beaches, some people were clouded out, others saw all of totality, others saw just a portion of the main event. It was hit and miss. From home at Oak Beach we might have seen it but only just. We were very happy with our decisions to move and flexibility to be able to do so.

I’ll post some close-up shots of the eclipse shortly.

Tonight, we party!

– Alan, November 14, 2012 / © 2012 Alan Dyer

 

Our Eclipse Group at Work


Nothing could be farther from an astrophoto than this, but this is what it takes to get a great shot – planning!

Here is our little group of Canadian eclipse chasers sitting around the patio table planning alternate viewing sites that we had inspected earlier that day on the Monday, two days before the eclipse. Maps, photos and weather forecasts all go into the mix to make a decision where best to be for the total eclipse of the Sun.

We found some good inland sites but getting to those would require leaving the comforts of home the afternoon before the eclipse to be in place for dawn on Wednesday and avoid driving the roo and cattle infested outback roads at night. We would prefer to stay on the beach, and weather prospects are improving. But if the eclipse had been this morning we would not have seen it from this location.

– Alan, November 13, 2012 / © 2012 Alan Dyer

 

Sign on the Centreline


I’m in eclipse country here, as the sign proclaims, just about on the centreline of the coming Moon’s shadow.

Today we drove 3 to 4 hours out onto what is called the Development Road or the Mulligan Highway, inland from the beaches where we are staying. This is the road that goes up to Cooktown (where Captain James Cook beached the Endeavour in 1770) from Port Douglas, but via the inland route. As you can see it is dry! That’s a good thing. While the coast was cloudy and rainy today, Monday, the inland sites we inspected were sunny, with word from the locals that the morning at eclipse time was perfectly clear. As it always is they promised us!

So we have some Plan B sites selected, and checked out with the local Queensland Police to make sure we’re OK to use them. However, weather forecasts for Wednesday morning at eclipse time are promising clear skies on the coast where we would prefer to stay in convenient comfort.

Not far from here, near the Palmer River Roadhouse, some 8,000 people have gathered in the dusty Outback for a festival of music and “new age healing.” We’re seeing lots of the participants on the road (often driving beat-up vans) looking like they’ve been transported by time machine from the 1960s and Woodstock. Eclipses attract many people of all interests to the track of the Moon’s shadow. Good luck to them … and us, two days from now.

– Alan, November 12, 2012 / © 2012 Alan Dyer

 

Two Days to Go Until the Eclipse


This was the sky at eclipse time, two days prior to the total eclipse of the Sun.

Had the eclipse been today we likely would have missed it. The Sun broke through briefly but minutes later the rain seen here off shore was over us. But a few minutes later it was clear and sunny again. It will be a game of chance to be sure.

Today, we travel inland to scout out viewing sites 3 hours away over the Dividing Range on the Development Road as a Plan B.

– Alan, November 12, 2012 / © 2012 Alan Dyer

 

On the Beach — Stargazing


This is stargazing in the tropics — on the beach, in shorts and sandals.

Here’s some of our eclipse chasing group enjoying a view of the southern hemisphere night sky, albeit though clouds. Jupiter is the bright object at left, Orion is rising on his side in the middle, Sirius is just above our stargazers, while Canopus is at far right. The Pleiades is at far left. We’re looking east, from a latitude of 16° south of the equator, where the sky takes on a completely new appearance that baffles and delights even seasoned northern stargazers.

– Alan, November 11, 2012 / © 2012 Alan Dyer

 

Three Days to Go Until the Eclipse


Skies and spirits brightened this morning as we were greeted to a wonderfully clear sunrise.

I took this moments ago on the morning of Sunday, November 11, three days before the total eclipse. If the eclipse had been this morning we would have seen it in grand style.

Nevertheless, we will continue our scouting of inland locations over the Dividing Range, at sites some 2 to 3 hours drive away. If the weather forecast looks gloomy the day before we will make a run for it inland but will have to make that call the afternoon before the eclipse to avoid driving in the dark with roos on the road. The eclipse happens an hour after sunrise on Wednesday, with the Sun a little higher than its position here. Ideally, we watch the eclipse from where I took this photo! But one must always have a Plan B and C in pocket.

– Alan, November 11, 2012 / © 2012 Alan Dyer

 

Four Days to Go Until the Eclipse


 

This is sunrise, four days before the November 14 total eclipse of the Sun, from our preferred viewing site on the coast of Queensland, Australia.

In four days, the Moon, which you can see as a waning crescent at upper left, will pass across the face of the Sun.

We’re here at our Beach House at Oak Beach, just south of Port Douglas, right on the eclipse centreline. The site is fantastic and we may have the beach pretty much to ourselves, or at least just for the residents of the beach houses long Oak Beach Road. However, the clouds are worrying. A system moving through is blanketing the area in cloud but promises to move off by eclipse morning. The total eclipse occurs about an hour after sunrise. So this is the view we’ll have, though we have a kilometre of beach to pick from.

However, we just spent one of several days scouting out alternative Plan B sites along the coast and inland. Mobility is often the key to success when chasing eclipses. It is a chase after all, and being able to see an eclipse right from your front yard (or in our case, front beach) is always the ideal plan. But plans often change.

There are lots of eclipse chasers here — about 40,000 have converged on Port Douglas area, which even at peak tourist season (which it is not now) handles only 10,000 people at a given time.

– Alan, November 10, 2012 / © @ 2012 Alan Dyer

 

Crossing the Tropic of Capricorn


Today on my drive north to the path of the November 14 total eclipse in Australia, I crossed the Tropic of Capricorn and am now officially in the tropics.

This is one of the many monuments that the demarcates this important line around the world, all located at 23.5° south latitude (or thereabouts). This one is in Rockhampton, Queensland. It’s actually at 23° 23′ 59″ S but that’s close enough for tourists. For photos of other Tropic of Capricorn monuments see Wikipedia’s page.

The Tropic of Capricorn is one of the world’s four main lines of latitude defined by the tilt of the Earth: The Arctic and Antarctic Circles at 66.5° N and S, and the Tropics of Cancer and Capricorn, at 23.5° N and S. The names for the Tropic lines come from the two constellations where the Sun used to be located millennia ago on the June and December solstices: Cancer and Capricornus. The precession motion of the Earth’s axis has since moved the Sun into Gemini and Sagittarius on those key annual dates.

The Tropic of Capricorn is the southernmost latitude on our planet where the Sun can appear directly overhead at the zenith, and then only on one day, the December solstice. I was here close to that date a few years ago and can attest to the lack of shadows at “high noon” at solstice on a Tropic line.

The zone on Earth between the two Tropic lines, between 23.5° N and 23.5° S, is of course called the Tropics. While the Sun may not always be overhead in the tropics it certainly is always high at mid-day. And hot!

Next stop: Magnetic Island, named by James Cook in 1770 as he thought the island was affecting his compass in strange ways.

– Alan, November 6, 2012 / © 2012 Alan Dyer