The competition, which is run by the Royal Observatory Greenwich in association with BBC Sky at Night Magazine, is now in its sixth year and has received over 2,500 entries. Photo: Centre of the Heart Nebula by Ivan Eder (Hungary). Situated 7500 light years away in the “W”-shaped constellation of Cassiopeia, the Heart Nebula is a vast region of glowing gas, energized by a cluster of young stars at its centre. The image depicts the central region, where dust clouds are being eroded and moulded into rugged shapes by the searing cosmic radiation. (Photo by Ivan Eder)

Coloured X-ray of a barn owl. A physicist has used X-ray to create an extraordinary collection of artwork. Arie van't Riets pictures reveal birds, fish, monkeys and flowers in an incredible new light. The 66-year-old, from Bathmen in the Netherlands, began X-raying flowers as a means to teach radiographers and physicians how the machine worked. But after adding a bit of colour to the pictures, the retired medical physicist realised the potential for an exciting new collection of art. (Photo by Arie van't Riet/Barcroft Media)

Divers swim beside millions of silverside fish at Devil's Grotto, Cayman Islands. Swimming in unison, millions of silverside fish dwarf the divers. The fish create waves of silver light as they move around the grottos that lie beneath the surface of the Caribbean Sea. These amazing photographs were captured by Belgian photographer Ellen Cuylaerts, 44, on a diving trip to the Devil's Grotto, Cayman Islands. (Photo by Ellen Cuylaerts/This is Guavo Media)

Dutch artist Daan Roosegaarde paid homage to Vincent Van Gogh's famous “Starry Night” painting by creating a glowing bike path relying on solar-powered LED lights. The 650-yard route which opened November 12, 2014 extends between Eindhoven and Neunen, Netherlands, where Van Gogh spent part of his life. Its the first event marking the 125th anniversary of Van Gogh's death July 29, 2015. (Photo by Pim Hendriksen/Studio Roosegaarde)

Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)

An image produced by the Hubble telescope of the perfectly “edge-on” galaxy, or NGC 4013, March 1, 2001. This new Hubble picture reveals, with great detail, huge clouds of dust and gas extending along, as well as far above, the galaxy's main disk. NGC 4013 is a spiral galaxy, similar to the Milky Way, lying some 55 million light-years from Earth in the direction of the constellation Ursa Major. Viewed face-on, it would look like a nearly circular pinwheel, but NGC 4013 happens to be seen edge-on from our vantage point. Even at 55 million light-years, the galaxy is larger than Hubble's field of view, and the image shows only a little more than half of the object, albeit with unprecedented detail. (Photo Courtesy of NASA/Newsmakers)

Mariam Ashraf, a teacher and “natural hair influencer”, speaks before a phone on a tripod and lights during a live-stream at her home in Egypt's capital Cairo on March 22, 2022. “Shaggy”, “messy”, “unprofessional”. Natural curls were once looked down upon in Egypt, where Western beauty standards favoured sleek, straight locks. Now, things are changing. (Photo by Khaled Desouki/AFP Photo)

Swab Cadet Langton reads the Running Light guidebook as members of the US Coast Guard academy class of 2026 report for the first day of Swab Summer, a seven-week training programme designed to transform civilian students into military members, in Connecticut on June 27, 2022. The Swabs, as the new cadets are called, cycle through haircuts, uniform issue, drill practice and various administrative in-processing over the course of the day. (Photo by Sean D. Elliot/AP Photo)