Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   This spectacular image shows a range of prominent constellations visible in the night sky over the desert of inner Mongolia, taken in August 2019. The yellowish star in the bottom left side is Arcturus, one of the brightest stars in the night sky, and the brightest in the constellation Boötes. The handle of the Big Dipper points towards this bright star and the Dipper is also visible above Boötes. The Northern Dipper (Bei Dou) is a traditional Chinese constellation. It is considered a chariot in which the Judges for Nobility are sitting. Arcturus is considered a single-star asterism, named the Horn, which forms part of the Chinese super-constellation for the spring, the Azure Dragon of the East. The front of the Northern Dipper points towards the star at the top of the photograph which is now called Polaris, the northern Pole Star. In ancient China, there was no bright star at the pole, so the stars in the nearest vicinity of the pole were considered to belong to the emperor and his family in the constellation the Purple Forbidden Palace. At least as early as mediaeval times, Polaris was considered part of the constellation of the Great Emperor of Heaven. Corona Borealis is also visible in the top right corner of this image, although not in its completeness. It is called the Coiled Thong in China. With its characteristic semi-circular shape, this is one of the smaller constellations of the 88 modern ones, but also can be traced back at least three or four millennia through the Roman “Crown”, the Greek wedding “Wreath”, and the Babylonian “Asterism of Dignity”. The modern name literally means “Northern Crown” in Latin. At the upper-right edge of the image, we find the part of the modern constellation Cassiopeia that is considered the Flying Corridor and an Auxiliary Road in ancient China. The W-shape of Cassiopeia is cut off by the edge of the photograph but the constellations to its south and southeast, Andromeda and Perseus, are clearly recognisable. Prominently we see the Andromeda galaxy, the most distant object that is visible to the unaided eye. It is located at the outermost outliers of the band of the Milky Way, which could explain why it has not been mentioned explicitly in ancient star catalogues, as it was mistakenly thought to be part of the Milky Way. The photograph also shows clearly reddish parts of the Milky Way that don’t appear bright to the naked eye, and also open clusters that are formed from the same molecular cloud, i.e., groups of stars with similar ages. This region is part of many big and small asterisms in traditional Chinese uranology.
Credit: Likai Lin/IAU OAE

Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   As Earth moves around the Sun, the positions of the stars in the night sky appear to change over the course of the year. This is well exemplified in this mosaic, with images taken in all four seasons throughout 2020 in the region of Veneto, Italy, showing the apparent motion of the Ursa Minor and Ursa Major constellations. Ursa Minor, the Little Bear, is a constellation of the northern hemisphere, and it contains the northern celestial pole, in our current epoch marked by a bright star called Polaris or the Pole Star. For centuries Polaris has been used for navigation in the northern hemisphere, as it has been almost at the exact pole position for roughly 200 years. In the Middle Ages and antiquity, there was no pole star; the celestial north pole lay in a dark region and the Greeks considered the “Little She-Bear” as a companion of the “Great She-Bear”, which is more easily recognizable. The brightest stars of these constellations were alternatively also considered as chariots by the Greeks, as written in Aratus’s famous didactic poem from the 3rd century before the common era. The most famous asterism in Ursa Major, composed of seven stars, has different names across the (northern) world. While considered as a chariot by the Greeks, it is “The Northern Dipper” in China, and “The Seven Oxen” for the ancient Romans. It was also the navigational purpose that led to the name The Great She-Bear, Ursa Major; for the Greeks, travelling towards the direction of the horizon above which Ursa Major appears meant moving towards the land of the bears (northern Europe). An animal is clearly recognizable when taking into account all the fainter stars in the vicinity of the seven bright ones. They considered it a female bear because Greek mythology connects this animal with the nymph Callisto, whose story describes the initiation rituals for women. In the top left, we see an image taken on a spring evening, while the image below shows the same portion of the sky on a summer evening. Going counterclockwise, we see the sky during autumn in the bottom right image, while the top right finally shows this portion of the sky in the winter. Note that the relative positions of Ursa Minor and the Big Dipper don’t change, but all stars appear to be moved in a circle around Polaris. This star pointing due north lies at the point where Earth’s rotational axis intersects the celestial sphere. The shift of constellations throughout the year is therefore a globe-clock or a globe-calendar, used by ancient civilizations to measure the year, and to predict the changes of seasons. It helps to establish, for instance, the best time for sowing and sailing as winds change with the seasons.
Credit: Giorgia Hofer/IAU OAE

Caption: 這段延時攝影記錄了2020年7月拍攝的三幀畫面中標誌性的北斗七星的軌跡。影像在意大利的三個地點拍攝：拉瓦雷多三峰（Tre Cime di Lavaredo）奧隆佐迪卡多雷、裡特山（Monte Rite）奇比亞納迪卡多雷，以及拉佐牧場（Casera Razzo）維戈迪卡多雷。這場視覺奧德賽展示了北斗七星的迷人軌跡，並在夜空中繪製出天體畫卷。它不僅描繪了這個著名星群的軌跡，還捕捉到2020年7月照亮天空的罕見新智彗星 C/2020 F3 這一非凡的天文事件，為我們的夜空增添了光彩。
Credit: 喬爾賈·霍弗/國際天文學聯合會教育辦公室 (CC BY 4.0)

Caption: 這段延時攝影捕捉了來自國家天體物理研究所 (INAF) 的 64 米撒丁島射電望遠鏡 (SRT) 周圍的恆星運動，特別是在天球背景下著名的北斗七星。隨著飛機飛過和射電望遠鏡旋轉，著名的北斗七星在天空中下沉，鏡頭也隨之移動。恆星的軌跡與射電望遠鏡的巨大天線之間的和諧互動，為 2019 年 9 月拍攝的宇宙芭蕾譜寫了一曲令人著迷的視覺頌歌。
Credit: Antonio Finazzi/IAU OAE (CC BY 4.0)

Caption: 北斗七星優雅地移動於加利福尼亞州莫諾湖超凡脫俗的凝灰岩層之上。延時攝影捕捉了北斗七星穿過北方地平線直至下合的過程。在莫諾湖的緯度（+38°）上，北斗七星的星星幾乎都是環極星，除了阿爾凱德（Alkaid）。北極星位於地平線之上38°的位置，正好在視野的右上角之外。月光將大地籠罩在柔和的光暈中，隨著月亮落下，光暈逐漸變暗，整個場景陷入黑暗之中。
Credit: Fabrizio Melandri/IAU OAE (CC BY 4.0)

Caption: A cosmic journey unfolds across continents in this time-lapse video which captures both iconic constellations from diverse corners of the world. Starting in China, the Big Dipper graces the night sky, a steadfast guide embedded in cultural narratives. Its luminance marks the beginning of this celestial odyssey. The two pointer stars on the end of the Big Dipper point to the North Star (Polaris) which appears to remain stationary as the sky rotates. From Nepal’s lofty peaks, the Big Dipper’s familiarity persists, a reliable fixture in the shifting panorama of the rotating planet. Moving to Chile, the Southern Cross adorns the firmament, emblematic of the southern skies. Frames from Chile showcase this constellation accompanied by the Milky Way Galaxy. In Namibia, a telescope from the H.E.S.S. Observatory appears in the video. Later, nestled beneath sheltering trees, the Big Dipper persists in its celestial prominence, appearing against a canvas of stars. Using varied techniques — fisheye lenses, static cameras, and Earth's movement-tracking — each frame unveils the Cross’s grandeur against diverse landscapes. These sequences — marked by star trails and Earth’s rotation—highlight the enduring presence of the Big Dipper and Southern Cross, bridging cultures and celestial beauty across hemispheres.
Credit: Jianfeng Dai/IAU OAE (CC BY 4.0)

Caption: 2022 年 3 月拍攝的這張照片中，北京故宮矗立在星軌編織的夜空芭蕾之下，見證著古老的天體之間的聯繫。紫禁城在設計時考慮到了宇宙的排列，呼應了北極星的方位，北極星又叫 Polaris，是長期以來指引航海者的天體之錨，象徵著天空的穩定。人們相信皇帝是北極星在人間的化身，是連接天地的橋梁。在這張用智能手機拍攝的和諧的一小時曝光照片中，星星的軌跡描繪了它們夜間穿越蒼穹的旅程，它們向北極星匯聚，體現了建築設計和天體軌跡的精確性。
Credit: Stephanie Ziyi Ye/IAU OAE (CC BY 4.0)