A woman strikes a police truck with her hand during a protest march in Santiago, Chile, Thursday, April 16, 2015. Thousands of students marched through the streets of Chile's capital to protest recent corruption scandals and to complain about delays in a promised education overhaul. While it was largely peaceful, violence broke out at the end when hooded protesters threw rocks and gasoline bombs at police. (Photo by Luis Hidalgo/AP Photo)

A model stands next to a BMW X6 AC Schnitzer car at Auto China 2012 in Beijing in this April 24, 2012 file photo. Amid the razzmatazz, music and crowds at the Shanghai autoshow on Monday, hundreds of attractive young women, and men, mingled among the stands and company booths, introducing the newest sedans and handing out pamphlets. For years, models have been a staple at China's big autoshows – as much of a draw as the latest car models themselves. 2015 is different – the organisers have banned models from the Shanghai show. (Photo by Jason Lee/Reuters)

An aspiring Catholic priest Jose Luis Guerra, a member of Raza Nueva in Christ, a project of the archdiocese of Monterrey, and other missionaries hand out a Bible to Angel Castillo, who wants to become a missionary with Raza Nueva, in the municipality of Garcia, outskirts of Monterrey, Mexico, July 12, 2016. In the troubled fringes of the northern Mexican city of Monterrey, an aspiring priest is using his faith to reach out to young gang members and at-risk youth, and bring them into his “Gang of Christ”. (Photo by Daniel Becerril/Reuters)

Sally Gomez drives to rescue of friend Michele Moore in flooded parking lot at Hyannis, Mass., September 9, 1969, after torrential rains of Hurricane Gerda flooded low areas of Cape Cod. Ann Davis of Osterville stands up in roof opening to lend a hand. Sally and Michele are from Centerville on the Cape. (Photo by Frank C. Curtin/AP Photo)

Winti spiritual leader Ramon Mac-Nack (2nd L) looks on as as his bride Melissa Karwafodi (2nd R) hands a gourd to a Maroon priest (L) as they are wedded in the first Winti marriage ever to be held in public, in district Para, Suriname, November 16, 2015. The Winti religion, which formed centuries ago out of elements of different religious traditions that African slaves brought with them to Suriname, was considered a form idolatry and prohibited by law since the days of slavery until it was finally officially recognized in 1971. (Photo by Ranu Abhelakh/Reuters)

Chinese aids activists hand out condoms in a subway train in Wuhan, central China's Hubei province on December 1, 2014. The World Health Organization issued a call to action to China on December 1, 2014 over HIV/AIDS as government figures said nearly half a million people are living with the disease or its precursor, with hundreds of thousands more thought to be undiagnosed. (Photo by AFP Photo)

Krystian Herba, a Polish extreme cyclist jumps up the steps of Eureka Tower on a bicycle as he breaks a Guinness World Record at Eureka Tower on February 4, 2014 in Melbourne, Australia. Herba jumped up 2,919 steps on his bicycle in 1 hour 45 minutes without supporting himself with his hands or feet to break his own Guinness World Record. (Photo by Scott Barbour/Getty Images)

“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)