Sidewalk Astronomy Tonight in Hamilton

Following weeks of miserable weather for astronomers, tonight and tomorrow night look marvellously clear in the Hamilton area. You can follow that sort of thing on-line every day in detail with the Clear Sky Chart web site: http://cleardarksky.com/c/Hamiltonkey.html (Dark blue is “good”).

Tonight, recommended is a view of Saturn, which will be due south of us at 10 PM, at a bit over 35 degrees above the horizon. The moon is waxing (getting fuller) and just past 50% illuminated. It will be a bit to the west of Saturn tonight. A modest telescope should show Saturn’s rings and some of the moons; binoculars will show the creamy overall colour of the planet but the rings will not be visible.

If you are mobile you might like to join the Hamilton Amateur Astronomers tonight at the T. B. McQuesten Park (corner of Upper Wentworth and the Linc) for some “Sidewalk Astronomy.” Members come out with telescopes on nice nights to give free demos to the public. I’m planning on arriving a little before sunset, perhaps 8:45.

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High Dynamic Range – Into Visual Fantasy

I like to say that what we see depends on how we look. No matter how much we may think that a photograph is a “real image” and what you see is “just they way it looked,” photographs are always interpretations, full of assumptions, conventions, and the ever-present interplay among art, technique, and technology. This is particularly true in astrophotography.

Even the stunning images taken by telescopes such as the Hubble Space Telescope are actually highly artificial. Not only do they represent magnifications far beyond what our own eyes can achieve, they also are made possible by gathering light from fantastically feint objects. Furthermore, they usually represent an artificial spectrum, a selection of colours represented on the image that are not the “natural” appearance of an object at all. Astrophotographers, artists, and anyone else working with these images can select various wavelengths of light that were captured by the original camera and transpose them into what we see in the final image.

That’s all by way of introduction to the following image, which I made on the evening of 14 June 2013. It’s a High Dynamic Range rendering of the moon, generated from three different photos taken in succession but at very different exposures. One exposure was short enough to capture details in the sunlit areas to the right; one was long enough to capture “earthshine” on the left. Merged together in the computer, they make a stunning image – not what you see of the moon at night with your eyes, but the moon none the less. In this rendering, I have exaggerated colours for effect:

Moon in HDR

Two faces of the moon. A High Dynamic Range image made by combining three photos taken on 14 June 2014 at different exposures. The sunlit side, on the right, is many times brighter than the earth-lit side on the left. Photographed with a Nikon D800 body on a Meade 125TB Maksutov Cassegrain telescope, on an EQ4 motorized mount. The earthlit side was exposed at ISO 800 for 10 seconds. The sunlit side consisted of two shots at 1/3 and 1/30 second. The three images were combined with Dynamic-Photo HDR.

High dynamic range imaging does not have to result in “garish” images, however. The original intent of the method was to make more detail in shadow and in highlight visible. Here’s another rendering from the same evening that is a little more “realistic” but was prepared, essentially, the same way:

HDR2

The moon on the evening of 14 June 2013 – with both bright side and earthlit side represented in an HDR image.

Copyright © 2013 David Allan Galbraith

Happy Golden Anniversary Valentina Tereshkova

It is truly sad, but there are some people out there – perhaps more than I’d like to believe, who apply labels to others in an attempt to keep them from achieving their dreams. We all win when someone breaks the mould and flies high. Today, 16 June 2013, is the 50th anniversary of Soviet cosmonaut Valentina Tereshkova piloting Vostok 6 into space. On 16 June 1963, she became the first women in space, and not as a passenger, either – but as a fully trained, capable space-farer.

According to the Wikipedia entry for General-Major Tereskova (http://en.wikipedia.org/wiki/Valentina_Tereshkova), who was know by her airforce handle “Sea Gull,” she has another very interesting distinction (among many). After her two day 1963 space flight she married Cosmonaut Andrian Nikolayev, who flew twice in space himself. Their daughter, Dr. Elena Andriyanovna, is the only person to have parents who were both space travellers (at least so far).

Since General-Major Tereshkova’s ground-breaking (or should I write “space-breaking” instead) flight 50 years ago, a total of 56 women have flown in space. The largest number of these have been aboard the US Space Shuttle, and Canada is very proud to have had two women astronauts to date, too (Dr. Roberta Bondar and Julie Payette).

These path-finding women prove that categories such as male and female do not limit or define what we can do as humans. At least, they should not. Unfortunately for many people, these categories and others such as ethnicity, spiritual or religious tradition, nationality, sexual orientation, or physical or mental abilities, are used as labels to define – and curtail – the aspirations of others. That kind of limited thinking is a form of bullying that our world cannot afford any longer. Let’s hope that the legacy of “Sea Gull” and all space pioneers is a world where our frontiers as individuals and as a species are not limited by anything other than the sizes of our hearts as we rise to meet challenges and fulfil our own potentials.

Copyright © 2013 David Allan Galbraith

One Day, If We Not Destroy Ourselves…

… we will venture to the stars. A still more glorious dawn awaits, not a sunrise, but a galaxy rise. The rising of the Milky Way.

The sky calls to us indeed.

These words are from the musical composition “A More Glorious Dawn” featuring the worlds of Carl Sagan and Stephen Hawking, arranged by melodysheep, AKA John D. Boswell. In his series of compositions entitled “Symphony of Science,” Boswell has certainly struck a chord with me. The tune runs through my head, like many an ear-worm. Over the past couple of weeks, however, it’s been running particularly deep.

At the end of May 2013 I had the privilege of spending a week or so in Arizona. The past six or eight months have been a time of rediscovery for me in several ways. I guess it all started with getting an old, dusty box out of storage in the fall. You see, my father was an engineer, and a very gentle man, and was fascinated with astronomy, and aircraft, and boats, and photography, and so many other things, too.

When I was little Dad bought what was for the time a quite good home telescope – a 4.5″ reflector marketed under the brand name Tasco. It had rather wobbly wooden legs, and the finish on the German equatorial mount wasn’t terribly impressive, and it only had little 0.95″ eyepieces. But it worked. It worked well to show the brighter planets and the moon to whomever wanted to take a look.

Although he never joined an astronomy club, my father loved to introduce people to our neighbours in the solar system with this white 4.5 incher. He was especially fond of taking the telescope up to the family cottage and showing the neighbours around. Today, nearly 20 years after his death, and likely 30 years after he had the ‘scope out of its box, friends at the cottage still talk with me about my Dad and his telescope.

I pulled the old ‘scope out of storage last fall. It had been sitting around its Styrofoam and cardboard carrier for a long time. Something seemed to grab me when I took it out of the box and set it up. I’ve now used the old ‘scope a few times, and have even coaxed it into taking a few photos… something I dreamed of years ago but never accomplished.

It touched off something, putting the telescope together, re-familiarizing myself with the mount and all of its details. It prompted me to start looking up again. And, it fueled the flaring passion for the sky that has resulted in several things. For one thing, this blog was borne out of that renewed passion. For another, I now have quite a fleet of home telescopes, something I fear needs a bit of trimming, actually. Too much of a good thing?

And all of this led me, last week, to a remote inn south of Benson, Arizona. Sitting down in a chair out in the desert, I looked up at the sky, and started taking images of the stars with a camera and tripod. And I listened again to “A More Glorious Dawn” on with my iPhone. I was feeling a bit lonely. I listened to Carl Sagan’s wonderful voice and powerful words. And I wondered once more what it’s all for.

And then I remembered the words in the film Cosmos, based on Sagan’s first-contact novel. In the story an alien that projects itself the image of the protagonist’s father states that in all of their exploration of the galaxy, the only thing that makes it all bearable is each other.

Thanks Carl. Thanks Dad.

Copyright © 2013 David Allan Galbraith

Stars On (Or From) A Plane

At breakfast at a B&B in Arizona on the 1st of June, 2013, conversation ran to the use of airborne telescopes. NASA has long used astronomical telescopes mounted on aircraft. Most recently, SOPHIA (the Stratospheric Observatory for Infrared Astronomy) has been flying about in a converted 747. SOPHIA boasts a 2.5 meter reflecting telescope, and flies high enough that infrared astronomy becomes possible.

In the days preceding this chat, during my recent trip through Arizona with astronomy on my mind, a nice alignment of three planets had taken place. Mercury, Venus, and Jupiter have all been grouped more or less in a line visible just after sunset. I went out several times during my trip to see this lovely sight and get a few photos. On the way home from Arizona to Ontario, I happened to be in a west-facing seat on a jet between Detroit, Michigan, and Toronto, Ontario, flying between 9:50 PM and 11 o’clock or so on the evening of 1 June 2013. I was thrilled to see some of the planets still above the western horizon during this flight. Jupiter had just set, but I managed to get photos of Mercury and Venus, and even picked up some of the surrounding stars in Gemini and Aquila, too. My mind flashed back to the breakfast conversation of the day before.

Here’s one of  several photos I took from the plane on the evening, processed slightly for contrast and brightness to try to emphasize the stars and planets. Please click on each image to see them somewhat enlarged. The planets and stars will be easier to spot:

Stars visible from a jet liner

The stars are a little hard to see on this reduced copy one of a series of photos taken on the evening of 1 June 2013.  The view is from a Canadair Regional Jet looking out the left side of the plane. The middle of the view is a little north of west. The vertical fin is a winglet that decreases wing-tip turbulence and increases efficiency. Photographed with a Nikon D800, f/3.8, 1/13th second exposure, ISO “maxed”, at 29mm focal length on manual focus.

Once I had my feet on the ground, I processed the image a little to facilitate spotting stars, and then used the free planetarium proram Stellarium to see what was where at the time, place, and altitude I took the photos. Here’s a labelled version of the same photo:

Stars visible from a jet liner, labelled

Venus, Mercury and an assortment of stars were visible – and photographable – from a regional jet flying between Detroit and Toronto on the evening of 2 June 2013. I confirmed identities of the stars and two planets visible at this time, from this direction and altitude, using Stellarium, a wonderful free planetarium program. Venus is about 12 degrees north of due west in this image. Jupiter would have set a little while before this, roughly under the trailing edge of the wing. Please click on this image to see a larger version.

In these versions of the photo, Venus is hard to spot, and even the stars are not nearly as obvious as they are on the original, much larger image. I cropped out a section of the original image file, and adjusted the contrast and brightness to show Venus a bit better. Hereès the edited image, which is not reduced in resolution at all from the original D800 photo. The colors have also not been modified, but appear more intense because of the changes to brightness and contrast.

Colourful close-up of Mercury and Venus as seen from a plane

Mercury (top) and Venus (bottom) from the same frame as above. Might make a great wall-hanging!

My photos from a jet liner don’t compete of course with real airborne astronomy. However, its reassuring to know that the night sky sometimes can be there fore you even when you don’t quite expect it. Even at 10,000 meters.

Copyright © 2013 David Allan Galbraith