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)

A boy reaches for a ball on a creek clogged with plastic waste on April 15, 2023 in Caloocan, Metro Manila, Philippines. (Photo by Ezra Acayan/Getty Images)

A woman affected by tear gas is assisted during a May Day protest against austerity measures, in San Juan, Puerto Rico May 1, 2018. (Photo by Alvin Baez/Reuters)

Members of Siam Classic Dance Studio perform for onlookers at Haymarket on January 21, 2023 in Sydney, Australia. The Lunar New Year or Spring Festival marks the transition of the Chinese zodiac sign from one animal to the next. 2023 sees in the Year of the Rabbit, which begins on January 22. In Chinese culture, the Rabbit is a symbol of longevity, peace and prosperity. The festival is celebrated in Australia by the country's significant Chinese-origin minority, who follow much of the same traditions as the Chinese diaspora in the rest of the world. (Photo by Lisa Maree Williams/Getty Images)

American actor and politician Ronald Reagan stands behind his wife, actor Jane Wyman, who sits down to dinner, circa 1940s. She is seated between two unidentified men, both in military uniforms adorned with Arms Qualification medals, the man on the right with Sharpshooter and Marksman badges and the man on the left, a Captain, with Expert and Sharpshooter badges. Reagan wears a military uniform with Cavalry branch insignia and Wyman wears a black dress with stranded pearl necklace, and a black hat with a veil. (Photo by Hulton Archive/Getty Images)

In this image released on November 08, American singer-songwriter Alicia Keys performs for at the MTV EMA's 2020 on November 01, 2020 in Los Angeles, California. The MTV EMA's aired on November 08, 2020. (Photo by Rich Fury/Getty Images for MTV)

Aide Choque, wearing a mask amid the COVID-19 pandemic, jumps with her skateboard during a youth talent show in La Paz, Bolivia, Wednesday, September 30, 2020. Young women called “Skates Imillas”, using the Aymara word for girl Imilla, use traditional Indigenous clothing as a statement of pride of their Indigenous culture while playing riding their skateboards. (Photo by Juan Karita/AP Photo)

The 26th annual National Geographic Traveler Photo Contest is now accepting submissions. Official categories include: “Travel Portraits”, “Outdoor Scenes”, “Sense of Place” and “Spontaneous Moments”. The contest is accepting entries until June 30. Photo: “Forest lights”. Aurora Borealis over the forest of the Pyhae Luosto National Park, Finland. (Photo and caption by Nicholas Roemmelt/National Geographic Traveler Photo Contest)