Revolutions
This night was a rare one. The weather was completely clear with no winds, the moon had set, and the temperature was even in the positives. Conditions were perfect for stargazing, and I had to take advantage of it. The dead silence in these grassy hills outside of Buffalo was only interrupted by the occasional howl of a coyote. I pointed my camera north and took pictures for 90 minutes, which I combined into this star trail image. It shows the stars apparent motion caused by the Earth's rotation. Each star in the northern sky takes 24 hours (23:56 to be precise) to make a complete revolution in a counterclockwise direction. The height of the North Star (also known as Polaris) is always equal to the latitude - 44° in this case. Any star less than 44° away from Polaris is circumpolar, which means it never goes below the horizon. The red at the bottom of the picture was a very dim appearance of the aurora. I couldn't see it with my eyes.
- Copyright
- Kevin Palmer
- Image Size
- 6016x4016 / 32.6MB
- Keywords
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2018, astronomy, astrophotography, aurora, aurora borealis, blue, circular, clear, cold, evening, grassland, january, kevin palmer, night, nikon d750, north, north star, northern lights, path, petrified tree, polaris, red, rokinon 14mm f2.8, rotation, scoria hills, sky, snow, snowy, space, stack, starry, stars, startrail, trail, winter
- Contained in galleries
- Wyoming, Night Sky
