We place too much value into something as elusive as time. This is the lesson that Arina Pozdnyak, the creator of Perpetual Calendar, is trying to teach us. Days fly by, and even months are mere speckles of sand in an hourglass of eternity. People do not realize that the time given to us by fate cannot be measured using months or even years. It is measured using emotions and impressions. If a person lives to be 150 years old without experiencing any emotions, he might as well have lived one day, for all it’s worth. On the other hand, a person who lived an exciting, fulfilling life, read countless books and cherished every moment that he had, is actually the one who lived a longer life, even if in reality his flame was snuffed out much too soon. (Photo by Arina Pozdnyak)

These spectacular landscapes may look like something from another planet – but they are in fact colorful salt ponds which stretch for miles. Despite being better known for tech companies and expensive property – San Francisco, California is also home to this vibrant quilt of color spanning the South Bay Area. From eerie green pools to gothic shades of red the surreal landscapes are caused by the organisms or micro-algae living within them. Photo: Aerial view of the salt ponds in San Francisco, California. (Photo by Cris Benton/Caters News)

Rangoli, also known as kolam or Muggu, is a folk art from India in which patterns are created on the floor in living rooms or courtyards using materials such as colored rice, dry flour, colored sand or flower petals. It is usually made during Diwali, Onam, Pongal and other Indian festivals. They are meant to be sacred welcoming areas for the Hindu deities. The ancient symbols have been passed down through the ages, from each generation to the next, keeping both the art form and the tradition alive. Similar practices are followed in different Indian states: in Tamil Nadu, there is Kolam in Tamil Nadu; Mandana in Rajasthan; Chaookpurna in Chhattisgarh; Alpana in West Bengal; Aripana in Bihar; Chowk pujan in Uttar Pradesh; Muggu in Andhra Pradesh and others.

The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.

Some of the worlds most iconic cities have been photographed as youve never seen them before in the shape of tiny round planets. By using a pioneering method of aerial photography, each location can be now seen at a full 360 degree angle. After some skilful manipulation on Photoshop known technically as stereographic projection, each sweeping panorama is then turned into a small circular shaped image. Whether its the Eiffel Tower, The Empire State Building or the Shanghai Skyline, each image manages to show hundreds of miles of city landscape. Here: the French Riveria of Cannes, France. (Photo by Airpano/Caters News)

Fossilized whale bones are on display outside the Wati El Hitan Fossils and Climate Change Museum, a UNESCO natural World Heritage site, on the opening day, in the Fayoum oasis, Egypt, Thursday, January 14, 2016. Egypt has cut the ribbon on the Middle East's first fossil museum housing the world's largest intact skeleton of a "walking whale" in an attempt to attract much-needed tourists driven off by recent militant attacks. The construction of the much-hyped Fossils and Climate Change Museum was covered a 2 billion euros (2. 17 billion dollars) grant from Italy, according to Italian Ambassador Maurizio Massari. Its centerpiece is an intact, 37-million-year-old and 20-meter-long skeleton of a legged form of whale that testifies to how modern-day whales evolved from land mammals. The sand-colored, dome-shaped museum is barely discernible in the breathtaking desert landscape that stretches all around. (Photo by Thomas Hartwell/AP Photo)

Merit Prize Winner: “A Well Earned Rest in the Sahara”. This photo of Moussa Macher, our Tuareg guide, was taken at the summit of Tin-Merzouga, the largest dune (or erg) in the Tadrat region of the Sahara desert in southern Algeria. Moussa rested while waiting for us to finish our 45-minute struggle to the top. It only took ten minutes of rolling, running, and jumping to get back down. The Tadrat is part of the Tassili N'Ajjer National Park World Heritage area, famous for its red sand and engravings and rock paintings of cattle, elephants, giraffes, and rhinos that lived there when the climate was milder. Photo location: Summit of Tin-Merzouga, Tadrat, Tassili N'Ajjer National Park, Algeria. (Photo and caption by Evan Cole/National Geographic Photo Contest)