June 14, 2013 – The Amazing Sky

The centre of the Galaxy culminates over a starlit landscape on a night near the summer solstice.

This was last weekend, on the same night I took the images of the aurora and noctilucent clouds featured in the previous two blog posts. But toward the end of the shoot, I turned south to capture this scene, of the Milky Way over a grassy prairie field.

The landscape is lit only by starlight and by the glow of twilight and aurora to the north.

In the sky, the constellations of Scorpius and Sagittarius are peaking as high as they get for me in southern Alberta. The red giant star Antares is to the right while the bright star clouds toward the centre of our Galaxy are just left of centre. The sky is not dark because of the glow of perpetual twilight at this time of year near solstice.

Deep sky fans will note that the star cluster M7, the southernmost Messier object, is just clearing the horizon.

Remarkably, this is a mere 15 second exposure, at ISO 1600 but with the 24mm lens wide open at f/1.4. Normally I wouldn’t shoot at that wide an aperture as the images look too distorted at the corners of the frame. But for this shot I used the Canon 60Da camera – its cropped-frame sensor records only the central area of what the lens projects so it crops out the nasty stuff at the corners of the frame that would certainly have been detracting had I used the full-frame camera.

But shooting at f/1.4 allowed even this quickie 15-second shot to grab lots of detail in the Milky Way.