The Hubble Space Telescope is shown following its release from the space shuttle Discovery Wednesday, February 19, 1997. The Hubble Space Telescope, one of NASA'S crowning glories, marks its 25th anniversary on Friday, April 24, 2015. With more than 1 million observations, including those of the farthest and oldest galaxies ever beholden by humanity, no man-made satellite has touched as many minds or hearts as Hubble. (Photo by AP Photo/NASA)

Descendants of American Southerners Wearing Confederate-era dresses and uniforms dance during a party to celebrate the 150th anniversary of the end of the American Civil War in Santa Barbara d'Oeste, Brazil, Sunday, April 26, 2015. For many of the residents of Santa Barbara d'Oeste and neighboring Americana, in Brazil's southeastern Sao Paulo state, having Confederate ancestry is a point of pride and is celebrated in high style at the annual “Festa dos Confederados”, or “Confederates Party” in Portuguese. (Photo by Andre Penner/AP Photo)

An employee of the National Park Service takes a selfie with President Barack Obama, left, in the background meeting with the crowd after a tour of Everglades National Park on Earth Day, Wednesday, April 22, 2015, in Florida. Obama used the visit to warn of the damage that climate change is already inflicting on the nation's environmental treasures. (Photo by Lynne Sladky/AP Photo)

Hair artist and barber Nariko, 27, etches an image of Barcelona's Neymar on the head of customer Luiz Fernadez, 15, before the Champions League semifinal first leg soccer match between Barcelona and Bayern Munich, at his barbershop in Sao Vicente, near Santos, in Sao Paulo state May 6, 2015. Nariko, who was motivated to get into the profession by his grandfather and uncle, has been etching profiles of the famous onto the sides and backs of heads for about a year or so. (Photo by Nacho Doce/Reuters)

Chechen Interior Minister Ruslan Alkhanov greets participants of the military parade to mark the Victory Day in Grozny, Russia, May 9, 2015. Russia marks the 70th anniversary of the end of World War Two in Europe on Saturday with a military parade, showcasing new military hardware at a time when relations with the West have hit lows not seen since the Cold War. (Photo by Reuters/Host Photo Agency/RIA Novosti)

In this November 3, 2015 file photo, Afghan Taliban fighters listen to Mullah Mohammed Rasool, the newly-elected leader of a breakaway faction of the Taliban, in Farah province, Afghanistan. Despite US President Donald Trump’s pronouncement that there would be no talks with the Taliban following a series of deadly attacks in Kabul, officials say talks continue, but neither side trusts the other and neither believes the other negotiates independently. (Photo by AP Photo/Stringer)

As the world marks the International Day of the Girl Child, women's rights activists point to progress on a wide array of issues but say more needs to be done to protect girls from child marriage, sexual assault and other forms of exploitation. Here is a selection of pictures showing the daily lives of girls across the globe, all taken by female Associated Press photojournalists. Here: In this December 14, 2015, file photo, a young clown rides in the back of a car following a procession to the Basilica of Our Lady of Guadalupe in Mexico City. Hundreds belonging to various clown associations made their annual pilgrimage to the Basilica to pay their respects to the Virgin of Guadalupe, Mexico's patron saint. (Photo by Rebecca Blackwell/AP Photo)

A farmer is seen hanging from a tree during a rally organized by Aam Aadmi (Common Man) Party (AAP) in New Delhi April 22, 2015. The farmer hanged himself from a tree during a political rally in New Delhi on Wednesday, in what appeared to be a desperate protest against the hardship felt by many people scratching a living in rural India. Four people climbed the tree to try to save the man after he was seen hanging. (Photo by Adnan Abidi/Reuters)