“Himalayan Dog”. This dog just appeared out of nowhere and followed us for an entire week during our trekking trip in the Himalayan outback. He always used to sleep in front of our tent and guarded us in the nights. When I decided to get up at 4 a.m. to climb the next 5000 m peak for sunrise he accompanied me as well. On the top he was sitting for the entire 30 minutes on this place looking straight into the countryside. Photo location: Ladakh, India. (Photo and caption by Sebastian Wahlhuetter/National Geographic Photo Contest)

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)

This handout photograph taken and released by the Center for Volcanology and Geological Hazard Mitigation on April 17, 2024, shows Mount Ruang spewing hot lava and smoke as seen from Sitaro, North Sulawesi. A volcano erupted several times in Indonesia's outermost region overnight on April 17, forcing hundreds of people to be evacuated after it spewed lava and a column of smoke more than a mile into the sky. (Photo by Handout/Center for Volcanology and Geological Hazard Mitigation via AFP Photo)

A coil-shaped Helix Nebula showing a fine web of filamentary “bicycle-spoke” features embedded in the colorful red and blue ring of gas. At 650 light-years away, the Helix is one of the nearest planetary nebulae to Earth. A planetary nebula is the glowing gas around a dying, Sun-like star. (Photo by Reuters/NASA)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

The Villarrica Volcano is seen at night from Villarrica area, Chile on November 16, 2022. (Photo by Cristobal Saavedra Escobar/Reuters)

A handout photo made available by Indonesia's Center for Volcanology and Geological Hazard Mitigation shows hot lava spewing from Mount Ibu in North Maluku province, Indonesia, 04 July 2024 (issued 05 July 2024). The Center for Volcanology and Geological Disaster Mitigation (PVMBG) advises the community around Mount Ibu and visitors not to carry out activities within a radius of 2.0 kilometers and a sectoral expansion of 5 kilometers towards the crater opening in the northern part of the active crater of Mount Ibu. (Photo by PVMBG/EPA)