30 of the world's most iconic photographs

In this June 5, 1989 file photo, a Chinese man stands alone to block a line of tanks heading east on Beijing’s Changan Blvd in Tiananmen Square. The man, calling for an end to the recent violence and bloodshed against pro-democracy demonstrators, was pulled away by bystanders, and the tanks continued on their way. Over 7 weeks in 1989, student-led pro-democracy protests centered on Beijing’s Tiananmen Square became China’s greatest political upheaval since the end of the Cultural Revolution more than a decade earlier. AP Photo/Jeff Widener, File

Adolf Hitler (1889-1945) climbing steps between ranks of Nazis holding swastika banners at the Bückeberg Harvest Festival. Huge crowds can be seen in the background. The Nazis staged a Reich harvest festival at the Bückeberg annually from 1933 until 1937. Photo: The Print Collector/Print Collector/Getty Images

Intrepid steel workers atop the 70 story RCA building in Rockefeller Center get all the air and freedom they want by lunching on a steel beam with a sheer drop of over 800 feet to the street level. Image taken on September 20, 1932.

The Hindenburg disaster at Lakehurst, New Jersey, which marked the end of the era of passenger-carrying airships. Photo: Sam Shere/Getty Images

A mushroom cloud rises over Nagasaki in Japan as the United States detonated an atomic bomb over the city on August 9, 1945. 'Fat Man' was the codename for the bomb. The first atomic bomb that was dropped on Hiroshima on August 6, 1945 was named 'Little Boy'. Photo: Corbis via Getty Images

A hijacked commercial plane about to slam into the World Trade Center shortly before crashing into the landmark skyscraper on September 11, 2001 in New York. Photo: SETH MCALLISTER/AFP via Getty Images

A vulture watches a starving child on March 1, 1993 in Sudan. Photo by Kevin Carter/Sygma/Sygma via Getty Images

A Turkish police officer stands next to a migrant child’s body off the shores in Bodrum, southern Turkey, on September 2, 2015 after a boat carrying refugees sank while reaching the Greek island of Kos. The child’s name was Alan Kurni (born Aylan Shenu). Photo: NILUFER DEMIR/AFP via Getty Images

Apollo 8 view of earthrise over the moon. Photo: Time Life Pictures/NASA/The LIFE Picture Collection via Getty Images

This picture taken on July 21,1969 of astronaut Edwin E. Aldrin Jr. walking on the surface of the moon near the leg of the Lunar Module ‘Eagle’ and astronaut Neil Armstrong, during the Apollo 11 extravehicular activity (EVA). Photo: NASA/AFP via Getty Images

Lieutenant General A A K Niazi, Martial Law Administrator of East Pakistan, (center) signs the Surrender Document as Lieutenant General Jagjit Singh Aurora, Joint Commander of Indian and Bangladeshi Forces, (left) looks on December16, 1971 in Bangladesh. (AP Photo)

In this February 23, 1945 file photo, US Marines of the 28th Regiment, 5th Division, raise the American flag atop Mt. Suribachi, Iwo Jima, Japan. AP Photo/Joe Rosenthal

This is the FIRST photograph ever taken, or the earliest known surviving photograph made in a camera, was taken by Joseph Nicéphore Niépce, circa 1826 or 1827. The image shows a view from an upstairs window at Niépce's estate, Le Gras, in the Burgundy region of France. (Photo by Apic/Getty Images)

A train was set on fire by a Muslim mob in Godhra on February 27, 2002. As many as 59 Hindu kar sevaks returning from Ayodhya were burnt alive in the fire and this triggered the deadly Hindu-Muslim riots Gujarat. AP Photo/Stringer

South Vietnamese General Nguyen Ngoc Loan, chief of the National Police, fires his pistol into the head of a suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street, February 1, 1968, early in the Tet Offensive. AP Photo/Eddie Adams

Mohandas Karamchand Gandhi reading as he sits cross-legged on floor next to a spinning wheel which looms in the foreground as a symbol of India’s struggle for Independence, at home. Photo: Margaret Bourke-White/Time & Life Pictures/Getty Images

American President John F Kennedy (1917-1963) is struck by an assassin’s bullet as he travels through Dallas in a motorcade on November 22, 1963. In the car next to him is his wife Jacqueline (1929-1994) and in the front seat is Texas Governor John Connally. Photo: Three Lions/Hulton Archive/Getty Images

Funeral of Mahatma Gandhi after he was assassinated in the garden of Birla House, on January 30, 1948. Photo: Universal History Archive/ Universal Images Group via Getty Images

Fire breaks out at the Taj hotel in Mumbai on November 26, 2008. Nearly 80 people were killed in a series of shootings and blasts across Mumbai, when 10 Pakistani terrorists, armed men with automatic weapons and grenades, targeted two of Mumbai's top luxury hotels and the main Chhatrapati Shivaji railway station. Photo: PAL PILLAI/AFP via Getty Images

Vietnamese children flee from their homes in the South Vietnamese village of Trang Bang after planes dropped a napalm bomb on the village, located 26 miles outside of Saigon. 25 years later, the young girl running naked from her village, Phan Thi Kim Phuc, was named UNESCO goodwill ambassador. Photo: Bettmann/Contributor/Getty Images

Kar sevaks atop the Babri Masjid shortly before it was demolished on December 6, 1992 at Ayodhya. Photo: Sanjay Sharma/Hindustan Times via Getty Images

Indian photographer Pablo Bartholomew (L) poses with Dutch Foreign Minister Hans Van Den Broek in Amsterdam, April 14, 1985, after receiving an award for Best World Press Photo of 1984. Behind them is the winning entry, which shows a child victim in his native India of the Bhopal disaster, caused by a gas leak from the Union Carbide pesticide plant. Photo: Scanned from negative Reuters/E. Werner CMC

A view of the Loch Ness Monster, near Inverness, Scotland, April 19, 1934. The photograph, one of two pictures known as the ‘surgeon’s photographs,’ was allegedly taken by Colonel Robert Kenneth Wilson, though it was later exposed as a hoax by one of the participants, Chris Spurling, who, on his deathbed, revealed that the pictures were staged by himself, Marmaduke and Ian Wetherell, and Wilson. References to a monster in Loch Ness date back to St. Columba’s biography in 565 AD. More than 1,000 people claim to have seen ‘Nessie’ and the area is, consequently, a popular tourist attraction. Photo: Keystone/Getty Images

A man falls to his death from the World Trade Center after two planes hit the twin towers on September 11, 2001 in New York City in a terrorist attack. Photo: Jose Jimenez/Primera Hora/Getty Images

Marilyn Monroe on Subway Grate Film star Marilyn Monroe poses over a Manhattan subway grate as the wind blows her white dress up. Photographers capture the moment on camera, which takes place on September 16, 1954, during the filming of Seven Year Itch. Reportedly, Monroe’s husband Joe DiMaggio was displeased at the attention his wife received from the crowds. Bettmann/Contributor/Getty Images

Thich Quang Duc, a Buddhist monk, burns himself to death on a Saigon street on June 11, 1963 to protest persecution of Buddhists by the South Vietnamese government. AP Photo/Malcolm Browne

Conservation rangers from an anti-poaching unit work with locals to evacuate the bodies of four mountain gorillas killed in mysterious circumstances in the park, July 24, 2007, Virunga National Park, Eastern Congo. Photo: Brent Stirton/Edit by Getty Images

A building belonging to Sikhs burns in Daryaganj on November 2, 1984. Violence broke out in India in the wake of Prime Minister Indira Gandhi's assassination. Sikh alienation was deep and had dramatic consequences. On October 31, 1984, Indira Gandhi was assassinated by her two Sikh bodyguards, Beant Singh and Satwant Singh. The anger against Sikhs led to the terrible riots. (Photo: BEDI/AFP via Getty Images)

In this handout image provided by The White House, US President Barack Obama, Vice President Joe Biden, Secretary of State Hillary Clinton and members of the national security team receive an update on the mission against Osama bin Laden in the Situation Room of the White House on May 1, 2011 in Washington, DC. Obama later announced that the United States had killed Bin Laden in an operation led by US Special Forces at a compound in Abbottabad, Pakistan. Photo: Pete Souza/The White House via Getty Images

Muhammad Ali in action after first round knockout of Sonny Liston at St. Dominic’s Arena, to win the World Heavyweight Boxing title on May 25, 1965. Photo: Neil Leifer/Sports Illustrated via Getty Images