This is a disc of stars floating in space (our sun being one of them), yet it appears as pale band across the night sky going from lower right to upper left here. One way to visualize this is If you were an ant sitting on a spoke of a bicycle wheel, and turned to look back at the center of the wheel you would see the thickness of the inside rim spanning your horizon. Likewise the diagonal band going from upper left to lower right here is the “thickness” of the disc of our home galaxy seen from the inside.
The "galactic core" which is the star rich "bulge" of the disc lies on the bottom right corner above the rooftops, and at the tip of the constellation Sagittarius or the "teapot". The lower half of the diameter continues below the horizon visible from southern hemisphere. Somewhere behind the thick gas and dust obscuring the star light, lies a supermassive black hole around which a hundred billion stars in our galaxy rotate. The sun goes around that center once in 250 million years.
The house peeking from the left is where I live, and one can see a bit of one of my south-west facing bedroom windows. Sometimes when I am up at night I will stand behind this glass to check if the skies are clear of clouds to decide if it is worth the trip downstairs for a viewing or imaging session.
Though not my first Milky Way image, this is the first one where I am happy with the result. The Milky Way is faint to begin with and the sodium vapor street lights do not help. With naked eyes you see close to nothing of this. Or barely a hint of something that is not a cloud. I had to use a special in-camera filter - an Astronomic CLS ("city light suppression") filter which cuts out wavelengths from sodium and mercury vapor lamps used in cities while letting other light pass through. The lens which is a fast lens (Tokina 11-20 mm f2.8) and takes in about 110 degrees of the sky was specially bought for an intended Milky Way shot on a trip to the Grand Canyon.
In fact, I realized only a few years ago that the Grand Canyon was a designated an official dark sky sight and wanted to see our home galaxy with my own eyes and and phoograph it. Despite all my planning and designs, rain clouds and thunderstorms killed my imaging opportunity that night and I returned empty handed. This image was totally unexpected given the local light pollution.
In some ways it is more rewarding to know such cosmic grandeur is on display every night right above our homes and not just in exotic far away destinations. Below is a view of our cosmic abode, seen from my front porch of my earthly home.
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| The Milky Way seen from my front porch |
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