The Path of the Sun

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Créé pour l'OAE

Légende : 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.
Crédit : Frank Niessen/IAU OAE (CC BY 4.0)

Termes du glossaire: Equinoxe , Solstice , Solstice d'été , Trajectoire du soleil (Arc diurne) , Solstice d'hiver
Catégories : Astronomie à l'œil nu
Mots clés : astrophotography

Licence : Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Icônes

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The Eclipse Clock-Eclipse on a Polar Day

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Créé pour l'OAE

Légende : 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.
Crédit : Stephanie Ziyi Ye/IAU OAE (CC BY 4.0)

Termes du glossaire: Trajectoire du soleil (Arc diurne) , Eclipse solaire totale , Cercle polaire
Catégories : Astronomie à l'œil nu , Système solaire
Mots clés : astrophotography

Licence : Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Icônes

Ce fichier est sur Zenodo ( image 1.23 MB)

La dernière heure de la journée

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Créé pour l'OAE

Légende : Mention honorable au concours d'astrophotographie 2023 de l'UAI OAE, catégorie Images fixes de l'arc diurne du Soleil et solargraphes : La dernière heure du jour, par Fabrizio Melandri. Cette image, prise le 2 mai 1997 au lac Scaffaiolo en Italie, capture magistralement la descente du Soleil dans une séquence de reflets en miroir sur les eaux calmes. Cette représentation époustouflante du temps met en valeur la beauté froide de l'environnement et constitue un témoignage intemporel des instants fugaces de la dernière heure de la journée. Cette image reçoit une mention honorable dans la catégorie des images fixes des arcs diurnes du soleil et des solargraphes.
Crédit : Fabrizio Melandri/UAI OAE (CC BY 4.0)

Termes du glossaire: Trajectoire du soleil (Arc diurne)
Catégories : Astronomie à l'œil nu
Mots clés : astrophotography

Licence : Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Icônes

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When the Sun Bounces

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Créé pour l'OAE

Légende : First place winner in the 2023 IAU OAE Astrophotography Contest, category of Still images of sunrise and sunset location over the year. This image was taken at Norway's North Cape. Owing to the latitude of this location, the Sun never truly sets during the summer months, from around April to August. This results in the unique spectacle of continuous daylight, known as a polar day. This captivating series of images, taken in 2022, showcases the Sun's relentless journey across the horizon every 30 minutes. At its lowest point in the sky, the Sun does not set, but appears to bounce off the horizon. The globe on the far right in the photo stands as a sentinel, marking the northernmost point of the European continental mainland.
Crédit : Milos Obert/IAU OAE (CC BY 4.0)

Termes du glossaire: Trajectoire du soleil (Arc diurne) , Cercle polaire , Cercle arctique , Journée polaire
Catégories : Astronomie à l'œil nu
Mots clés : astrophotography

Licence : Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Icônes

Ce fichier est sur Zenodo ( image 3.54 MB)

Solstices and Equinox

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Créé pour l'OAE

Légende : 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.
Crédit : Tunç Tezel/IAU OAE (CC BY 4.0)

Termes du glossaire: Equinoxe , Solstice , Solstice d'été , Trajectoire du soleil (Arc diurne) , Solstice d'hiver
Catégories : Astronomie à l'œil nu
Mots clés : astrophotography

Licence : Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Creative Commons (CC) Attribution 4.0 International (CC BY 4.0) Icônes

Ce fichier est sur Zenodo ( image 1.71 MB)