Nature, singles winner: Frogs with their legs severed struggle to the surface, surrounded by frogspawn, after being thrown back into the water in Covasna, Romania. (Photo by Bence Mate/World Press Photo 2019)

A visitor stands in front of a portrait taken by artist Bruce Gilden at the “Masters of Photography” exhibition at the Photokina trade fair in Cologne on September 20, 2016. The fair for the photographic and imaging sector, that is running from September 20 to 25, 2016, presents products from image capture, image processing and storage to image output. Photokina also includes a program of events with congresses, workshops, symposiums and photography exhibitions. (Photo by Patrik Stollarz/AFP Photo)

“Panopticons is an arts and regeneration project of the East Lancashire Environmental Arts Network managed by Mid Pennine Arts. It involved the construction of series of 21st-century landmarks, or Panopticons (structures providing a comprehensive view), across East Lancashire, England, as symbols of the renaissance of the area”. – Wikipedia

Photo: “Singing Ringing Tree. The Singing Ringing Tree is a musical sculpture overlooking Burnley. It was designed by architects Mike Tonkin and Anna Liu of Tonkin Liu and constructed from pipes of galvanised steel”. (Photos by WandereringSoul/Mark Tighe)

This is the Legends Russian Series. Legends car exceeds new Porsche 911 power-to-weight ratio – it is 260 hp per ton with the car weight of 500 kg. It’s been designed in the USA by 600 Racing Inc, a subsidiary of Speedway Motorsport, the largest motorsport holding company in America with the annual turnover of $567,000,000. Khimki, Moscow region. February 11, 2012. (Photo by Alexey Petrov)

The Jet Propulsion Lab team's RoboSimian robot turns on a valve at a simulated disaster-response course during day one of the Defense Advanced Research Projects Agency (DARPA) Robotics Challenge finals in Pomona, California, June 5, 2015. (Photo by David McNew/Reuters)

Six year old Gillian Smith preparing for the All England Stage Dancing Competition where she has previously won five certificates and a silver medal in the under sevens category. (Photo by Terry Fincher/Keystone/Getty Images). 5th July 1957

The northeastern United States sweltered this week in a scorching summer heat wave, complete with stagnant, sticky air and no winds for relief, forecasters said. Even in a summer already filled with stretches of very hot weather, this week will be stubbornly brutal, with no relief in sight until the weekend brings thunderstorms to the region, they said. "Plain and simple, this week may feel the worst of any week for this summer in the Northeast," said Accuweather.com meteorologist Alex Sosnowski. (Reuters)

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.