April 1, 2019 – The Amazing Sky

Winter Sky Setting in Twilight at Dinosaur Park

There’s a slogan used in the U.S. National Parks that “half the Park is after dark.” It is certainly true at Dinosaur Provincial Park in Alberta.

Last Friday night, March 29, I spent the evening at one of my favourite nightscape sites, Dinosaur Provincial Park, about an hour’s drive east of my home. It was one of those magical nights – clear, mild, dry, and no mosquitoes! Yet!

I wanted to shoot Orion and the photogenic winter sky setting into the evening twilight over the Badlands landscape. This was the last moonless weekend to do so.

I shot some individual images (such as above) and also multi-panel panoramas, created by shooting a series of overlapping images at equal spacings, then stitching them later at the computer.

Winter Sky Setting at Dinosaur Park Panorama — This is a 240° panorama stitched from 17 segments, all with the 24mm Sigma Art lens and Nikon D750 in portrait orientation, each segment 20 seconds at f/1.4 and ISO 3200. Stitched with Adobe Camera Raw.

There’s a narrow window of time between twilight and full darkness when the Milky Way shows up well but the western sky still has a lingering blue glow. This window occurs after the normal “blue hour” favoured by photographers.

The panorama above shows the arch of the winter Milky Way but also the towering band of the Zodiacal Light rising out of the twilight and distant yellow glow of Calgary. Zodiacal Light is sunlight scattering off meteoric and cometary dust orbiting in the inner solar system, so this is a phenomenon in space not in our atmosphere. However, the narrow streak is an aircraft contrail.

Spring Sky Panorama at Dinosaur Park — A 360° panorama of the spring sky over the Badlands of Dinosaur Provincial Park, Alberta. This is a panorama of 12 segments taken with the 14mm Sigma Art lens and Nikon D750 in portrait orientation, all for 30 seconds at f/2.8 and ISO 4000. Taken at 30° spacings. Stitched with PTGui.

Later that night, when the sky was fully dark I shot this complete panorama showing not only the Milky Way and Zodiacal Light to the west, but also the faint arc of the Zodiacal Band continuing on from the pyramid-shaped Zodiacal Light over into the east, where it brightens into the subtle glow of Gegenschein. This is caused by sunlight reflecting off interplanetary dust particles in the direction opposite the Sun.

Both the Band and Gegenschein were visible to the naked eye, but only if you knew what to look for, and have a very dark sky.

The Winter Stars and Zodiacal Light at Dinosaur Park — This is a panorama stitched from 3 segments, all with the 24mm Sigma Art lens and Nikon D750, for 20 seconds at f/2.2 and ISO 4000. Stitched with Adobe Camera Raw.

A closeup shows the Zodiacal Light in the west as the subtle blue glow tapering toward the top as it meets the Milky Way.

It takes a dark site to see these subtle glows. Dinosaur Park is not an official Dark Sky Preserve but certainly deserves to be. Now if we could only get Calgary, Brooks and Bassano to turn down and shield their lights!

Spring Sky RIsing at Dinosaur Park Panorama — A 180° panorama of the spring sky and constellations rising in the east over the Badlands of Dinosaur Provincial Park, Alberta on March 29, 2019. This is a stitch of 6 segments, each with the 14mm Sigma Art lens and Nikon D750 in portrait mode, each 30 seconds at f/2.8 and ISO 4000. Stitched with PTGui.

A closeup facing the other way, to the east, shows the area of sky opposite the Milky Way, in the spring sky. The familiar Big Dipper, now high our spring sky, is at top with its handle pointing down to Arcturus and Spica (just rising above the horizon) – remember to “arc to Arcturus, and speed on to Spica.”

Leo is at right of centre, flanked by the Beehive and Coma Berenices star clusters.

Polaris is at left — however, the distortion introduced by the panorama stitching at high altitudes stretches out the sky at the top of the frame, so the Dipper’s Pointer stars do not point in a straight line to Polaris.

The faint Zodiacal Band is visible at right, brightening toward the horizon in the Gegenschein.

I shoot images like these for use as illustrations in future eBook projects about stargazing and the wonders of the night sky. Several are in the works!

Clear skies!