Category winner
SNR G107.5-5.2, Unexpected Discovery (the Nereides Nebula in Cassiopeia) by Marcel Drechsler, Bray Falls, Yann Sainty, Nicolas Martino and Richard Galli
"A new supernova remnant right on our doorstep! One team, 3,559 frames, 260 hours of exposure time, telescopes on three continents and one goal − not only to explore a supernova remnant that has not yet been discovered by science, but also to photograph it in an ambitious joint project," the team explain.
"Our international team of amateur astronomers under the scientific leadership of Professor Robert Fesen (USA) recently made a groundbreaking discovery. In the centre of the famous constellation Cassiopeia, the team has identified a previously unknown, gigantic supernova remnant (SNR).
"With an extent of three degrees (equivalent to six Full Moons side by side), it may be the largest SNR ever discovered by amateur astronomers. The fact that amateurs have made such a discovery is a testament to how important their role has become in today’s astronomy."
Taken in Oukaïmeden, Atlas Mountains, Morocco, Sierra Nevada Mountains, Auberry, California, USA, Avril, Meurthe-et-Moselle, Grand Est, France, Dommartin-lès-Remiremont, Vosges, Grand Est, France, Puzieux, Meurthe-et-Moselle, Grand Est, France and Turckheim, Haut-Rhin, Grand Est, France, 31 July, 1–4 August, 5–15 and 20 September, 6, 7, 9 and 15 October, 2–5, 7, 8, 10–12 and 16 November 2023
Runner-up
Serpens: a Mosaic by Mukund Raguram
"This three-panel mosaic of the constellation Serpens is my most ambitious endeavour in astrophotography to date," Mukund says.
"Serpens receives less attention than many other, more popular summer constellations, but its unique assortment of dark, reflection and planetary nebulae, and emission objects set against a gorgeous background of golden stars has made Serpens my favourite constellation in the night sky – and resulted in the best work of my astrophotography career. I plan to expand on this mosaic in the years to come, as there are still many beautiful secrets in Serpens to reveal."
Throckmorton, Texas, USA, 11, 17 and 21 April, 12 and 22 May, 8–11, 14–18, 20 and 26–29 June, 12–13 and 18 July 2023
Highly commended
Antares Region by Bence Tóth
"This image shows the dust and gas formations around the star Antares. As this part of the sky is barely visible from Hungary, I travelled to Namibia as part of an astrophotography expedition team to capture this image," Bence explains.
"To achieve this huge field-of-view, I used a telephoto lens instead of a long focal length telescope. Even at 135 mm I needed to create a five-panel mosaic (three panels RGB and two panels of H-alpha) to be able to show this huge region in one picture.
Taken in Isabis Farm, Namibia, 16–20 June 2023
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