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)

Hooded torch bearers lead the winter procession through the snow on February 4, 2012 in Huddersfield, England. Imbolc is a pagan festival that marks the half way point between the winter solstice and the spring equinox. Imbolc festivals celebrates the awakening of the land and the growing power of the Sun. (Photo by Bethany Clarke/Getty Images)

After some days with temperatures below freezing point, I was out skating at some lakes at the outskirts of Oslo in Norway. After a while I noticed something on the ice. To my astonishment it was a dead frozen frog.

Aerial view of a giant sinkhole on June 09, 2021 in Santa María Zacatepec, Mexico. The giant sinkhole is located 20 kilometers northwest from the capital city Puebla, the hole now measures 110 meters across its widest point, covering around 11,000 square meters and damaging a house built near the place where it appeared. Farmers of the surroundings have been affected since they are not allowed to enter their fields due to the warning perimeter set up by the authorities. (Photo by Hector Vivas/Getty Images)

A couple is walking hand-held up Kronsberg, just outside Hanover, Germany on April 7, 2020, when the moon rises on the horizon as the so-called supermoon. The moon reaches its perigee, i.e. the point closest to the Earth's orbit, on the night of 7-8 April as a full moon and therefore appears particularly large to the human observer. (Photo by Julian Stratenschulte/dpa via ZUMA Press)

Denis and Nelya, both 30, from Moscow, Russia invited brown bear Stepan along to their very special ceremony. As well as witnessing the couple exchange vows, the bear also played the role of registrar at one point. Denis said: “We both knew Stepan is a very kind bear but still it is a huge, unpredictable animal so we were a bit scared, but still happy to be able to make our dream come true. It was a fantastic experience to have this photoshoot with Stepan”. (Photo by Olga Barantseva/Caters News)

Nationalist youths throw bottles at police officers after the annual Orange march on July 12, 2016 in Belfast, Northern Ireland. The controversial Ardoyne interface is a flash point between the Catholic and Protestant communities with trouble flaring in the area frequently during the so called marching season. The Protestant Orange bands from the nearby area have been stopped from parading past the Catholic Ardoyne for the past three years. (Photo by Charles McQuillan/Getty Images)

A Perseid meteor streaks across the sky above Inspiration Point early on August 12, 2016 in Bryce Canyon National Park, Utah. The annual display, known as the Perseid shower because the meteors appear to radiate from the constellation Perseus in the northeastern sky, is a result of Earth's orbit passing through debris from the comet Swift-Tuttle. (Photo by Ethan Miller/Getty Images)