People commute during a heavy rain shower in Chandigarh, India, June 22, 2016. (Photo by Ajay Verma/Reuters)

People pour wine at each other during the traditional “Battle of Wine” held as part of the Haro Wine Festival in the La Rioja region in Haro, Spain, 29 June 2016. Every year on 29 June inhabitants and tourists celebrate San Pedro's day by trowing at each other thousands of liters of Riojan wine. (Photo by Abel Alonso/EPA)

A person poses on the track during a fashion competition at the Durban July horse racing event in Durban, South Africa, July 2, 2016. (Photo by Rogan Ward/Reuters)

Demonstrators perform a dance in front of riot policemen during a march called by students to request changes in the education system in Santiago, Chile September 5, 2017. (Photo by Ivan Alvarado/Reuters)

Iranian Shiite Muslim women gather around a bonfire after rubbing mud on their body during the “Kharrah Mali” (Mud Rubbing) ritual to mark the Ashura religious ceremony in the city of Khorramabad, some 470 kms southwest of Tehran, early in the morning on October 1, 2017. “Khrreh Mali” or “Mud Rubbing” is a ritual that is held in the city of Khorramabad every year to commemorate the seventh century slaying of Prophet Mohammed' s grandson Imam Hussein, in which Iranian men roll over in mud and dry themselves by gathering around the bonfires before flagellating themselves. (Photo by Atta Kenare/AFP Photo)

A Rohingya refugee woman is helped from a boat as she arrives exhausted on the Bangladesh side of the Naf River at Shah Porir Dwip after fleeing her village in Myanmar, on October 1, 2017 in Cox's Bazar, Bangladesh. (Photo by Kevin Frayer/Getty Images)

South Korean students pose for a selfie following a traditional coming-of-age ceremony at Namsan hanok village in Seoul on May 15, 2017. The Coming of Age Day is the day to celebrate and encourage the youth who have reached the age of 20, which is considered the beginning of adulthood. (Photo by Ed Jones/AFP Photo)

“The scientists behind NASA's $2.5 billion Curiosity rover mission on Mars on Tuesday explained the nature of a tiny, gleaming "flower" embedded in Red Planet rock, and revealed where they'll be using the SUV-sized robot's drill for the first time”. – Alan Boyle via NBCNews.com

Photo: Scientists say that a “Martian flower”, seen here in an image from the Curiosity rover's Mars Hand Lens Imager, is a 2-millimeter-wide grain or pebble that's embedded in the surrounding rock. Another, darker-colored mineral grain can be seen above and to the left. (Photo by NASA)