A weathered juniper tree in Montana’s northern Rocky Mountains is filled with arced star trails and in the centre sits Polaris, the brightest star in the constellation of Ursa Minor.
This image, by Jake Mosher of the United States, is one of those shortlisted in this year’s Insight Astronomy Photographer of the Year competition, organised by the Royal Observatory Greenwich.
The photographer said it took several test frames of long exposures to make sure that Polaris was in the right position, but eventually things lined up and the Moon provided enough light to the foreground, yet plenty of dark skies to allow a high enough ISO to capture lots of stars.
Winners from the 2018 competition will be announced on 23 October at a special awards ceremony. The following day, to celebrate the competition’s tenth year, a new gallery will open at the National Maritime Museum to display the winners alongside some of the best images from the last nine years.