The Path of the Sun

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Created for the OAE

Caption: Second place winner in the 2023 IAU OAE Astrophotography Contest, category of Still images of day arcs of the Sun and Solargraphs. This enchanting image, captured in Germany between 21 June 2018 and 21 December 2018, is a poetic blend of art and science, showcasing nature's rhythm and the passage of time. It combines images taken at different times of day over the course of six months. Each curve tracks the Sun’s path (or arc) across the sky on a particular day. The sweeping arc of the Sun is distorted here by the projection, making it appear like a curve. The position of the daily arc across the sky changes with the Sun’s seasonal movement in the sky. Captured using a simple pinhole camera fashioned from a coffee can, it shows the Sun's journey over the course of six months, and the gradual shift of the daily arc from the summer, when it is higher in the sky, to its lowest arc at the winter solstice. Gaps in the Sun’s path represent days or times of day when the Sun was obscured by clouds. This image is a vivid testament to the changing seasons, revealing the Sun's dance in the sky as days grow shorter or longer.
Credit: Frank Niessen/IAU OAE (CC BY 4.0)

Glossary Terms: Equinox , Solstice , Summer Solstice , Sun Path (Day Arc) , Winter Solstice
Categories: Naked Eye Astronomy
Tags: astrophotography

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

This file on Zenodo ( image 465.46 kB)

The Eclipse Clock-Eclipse on a Polar Day

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Created for the OAE

Caption: First place winner in the 2023 IAU OAE Astrophotography Contest, category of Still images of day arcs of the Sun and Solargraphs. Constructed by combining multiple images over the course of a 24-hour period, the image was captured in Union Glacier, Antarctica, during the total solar eclipse of 4 December 2021, and showcases the day arc of the Sun. It illustrates the unique phenomenon of a polar day, during which the Sun travels around the sky without setting. During polar days, areas within the polar circles experience 24 hours of continuous daylight, and the Sun doesn’t set for an extended period. The image also offers a rare perspective of a solar eclipse, where the Moon passes between the Sun and Earth, and as viewed from Earth. This can be seen in the lower image of the Sun, where the Moon covers the solar disc.
Credit: Stephanie Ziyi Ye/IAU OAE (CC BY 4.0)

Glossary Terms: Sun Path (Day Arc) , Total Solar Eclipse , Polar Circle
Categories: Naked Eye Astronomy , Solar System
Tags: astrophotography

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

This file on Zenodo ( image 1.23 MB)

The Last Hour of the Day

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Created for the OAE

Caption: Honorable mention in the 2023 IAU OAE Astrophotography Contest, category of Still images of day arcs of the Sun and Solargraphs. This image, taken on 2 May 1997 at Lake Scaffaiolo in Italy, masterfully captures the Sun's descent in a sequence of mirrored reflections on the placid waters. Its breathtaking representation of time showcases the serene beauty of the surroundings, and stands as a timeless testament to the fleeting moments of the day’s final hour.
Credit: Fabrizio Melandri/IAU OAE (CC BY 4.0)

Glossary Terms: Sun Path (Day Arc)
Categories: Naked Eye Astronomy
Tags: astrophotography

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

This file on Zenodo ( image 940.09 kB)

Solstices and Equinox

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Created for the OAE

Caption: Honorable mention in the 2023 IAU OAE Astrophotography Contest, category of Still images of day arcs of the Sun and Solargraphs. This captivating image showcases the journey of the Sun through the sky during the winter solstice (bottom), equinox (middle), and summer solstice (top) in Bursa, Turkey, between 21 December 2007 and 20 June 2008. Using a fisheye lens, the photographer captured the Sun's positions at regular intervals from sunrise to sunset on the three different days, illustrating the changing lengths of day and night throughout the year. The variations in the Sun’s daily path across the sky, its height at midday, and the positions of sunrise and sunset, as well as the length of a day, depend on Earth’s axial tilt relative to its orbit around the Sun. The series was taken from a rooftop in Bursa, where the local terrain adds its own unique touch by occasionally obstructing the horizon. Oriented with north at the top and south at the bottom, this visual diary serves as a stunning representation of the Sun’s path for those residing in mid-northern latitudes.
Credit: Tunç Tezel/IAU OAE (CC BY 4.0)

Glossary Terms: Equinox , Solstice , Summer Solstice , Sun Path (Day Arc) , Winter Solstice
Categories: Naked Eye Astronomy
Tags: astrophotography

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

This file on Zenodo ( image 1.71 MB)

Where the Sun Sets Every Month

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Created for the OAE

Caption: Third place winner in the 2023 IAU OAE Astrophotography Contest, category of Still images of sunrise and sunset location over the year. Taken with a smartphone from San Rafael, Bulacan, Philippines, this series of images capture the changing position of sunset over the year owing to Earth’s axial tilt and orbit around the Sun. From January to December 2022, each image reflects the changing backdrop and position of the Sun at dusk. Observe the changing foliage and the appearance of an electricity pole in October. This collection serves as a visual testament to the celestial dance between Earth and the Sun, and the natural transformations on the ground.
Credit: John Paul Pile/IAU OAE (CC BY 4.0)

Glossary Terms: Equinox , Solstice , Summer Solstice , Sun Path (Day Arc) , Winter Solstice
Categories: Naked Eye Astronomy
Tags: astrophotography

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

This file on Zenodo ( image 11.82 MB)