Jassen Todorov, 40, from San Francisco is a professor of music at San Francisco State University, but he took to helicoptering in his spare time. While he was content to keep the panoramic views he witnessed to himself, Todorov has now paired his passion for flying with photography to capture some of the United States’ undiscovered vistas. Here: Grand Prismatic Spring, Yellowstone, Wyoming. (Photo by Jassen Todorov/Caters News)

Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its (rare) pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. It streaks white, and its Mohs hardness varies between 3.5 and 4. Its specific gravity is between 3.5 and 3.7. It crystallizes in the trigonal system, and cleaves with rhombohedral carbonate cleavage in three directions.

HRP-4C, a five-foot humanoid robot developed at Japan's National Institute of Advanced Industrial Science and Technology, sings and dances with performers at the Digital Contents Expo in Tokyo on October 17, 2010. The robot runs entertainment software called Choreonoid, a name formed from the words “choreograph” and “humanoid”. (Yoshikazu Tsuno/AFP)

Michael O’Neill won a prize in animal portraits with fry of a peacock bass hovering around their mother for protection against predators in South Florida. (Photo by Michael Patrick O'Neill/2016 National Geographic Nature Photographer of the Year)

Children play underneath Jacaranda trees lining a street in the capital Harare, Zimbabwe, Friday, October 11, 2019. Zimbabwe now has the world's second highest inflation after Venezuela, according to International Monetary Fund figures. The economy has been on a downward spiral for more than a year as hopes fade that Mugabe's successor and former deputy, President Emmerson Mnangagwa, will deliver on his promises of prosperity. (Photo by Tsvangirayi Mukwazhi/AP Photo)

Kite-surfers practice in a water reservoir at the shores of the Mediterranean sea close to the southern Israeli kibbutz of Ziqim during stormy weather, on December 20, 2021. (Photo by Menahem Kahana/AFP Photo)

Two friends attempt to balance in the icy conditions in Newcastle, England on February 2, 2019. Boozy Brits across the UK took to the streets last night to ensure they got February off to a wet start after “Dry January”. (Photo by Craig Connor/North News and Pictures)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)