Balloons participate in the Balloon Spectacular during Canberra Festival on March 10, 2012 in Canberra, Australia. The annual balloon festival in Canberra is considered one of the best in the world, and is unique in allowing patrons to float above Parliament, embassies and other government buildings. Canberra is celebrating its 99th birthday in 2012, with over 50 events in the 17 day Canberra Festival. (Photo by Cameron Spencer/Getty Images)

In a north London hospital, scientists are growing noses, ears and blood vessels in the laboratory in a bold attempt to make body parts using stem cells. It is among several labs around the world, including in the U.S., that are working on the futuristic idea of growing custom-made organs in the lab. (Photo by Matt Dunham/AP Photo)

An activist takes a selfie during a protest ahead of the 2015 Paris Climate Conference, in Paris, Sunday, November 29, 2015. More than 140 world leaders are gathering around Paris for high-stakes climate talks that start Monday, and activists are holding marches and protests around the world to urge them to reach a strong agreement to slow global warming. (Photo by Christophe Ena/AP Photo)

Houthi followers perform the traditional Baraa dance ahead of a demonstration against the Saudi-led air strikes in Yemen's capital Sanaa August 24, 2015. The nothern-based Houthis, a Shi'ite Muslim group, took control of Sanaa last September. Arab countries intervened in the conflict in March to halt a Houthi advance into the south which caused the Saudi-backed government to flee to Riyadh from its refuge in the southern port of Aden. (Photo by Khaled Abdullah/Reuters)

To mark the occasion of International Women' s Day on March 8, 2018 AFP presents a series of photos depicting women performing roles or working in professions more traditionally held by men. Here: Professional wrestler Cristal (Crystal) poses for a photograph in her trainig place on February 09, 2018 in Mexico city, Mexico. (Photo by Omar Torres/AFP Photo)

A rainbow appears as people enjoy a warm afternoon on a tour boat at Niagara Falls in Ontario, Canada on October 21, 2024. (Photo by Mert Alper Dervis/Anadolu via Getty Images)

Young demonstrators (many shirtless) shout and cheer as they overturn a truck trailer in the Reflecting Pool on the Mall facing the Washington Monument during the “Honor America Day Smoke-In” thrown by marijuana activists to protest the official “Honor America Day” ceremonies being held at the Lincoln Memorial, Washington, DC, July 4, 1970. (Photo by David Fenton/Getty Images)

New York Jets running back La'Mical Perine fends off an airborne exercise ball thrown at him as he carries the ball during NFL football practice, Wednesday, June 2, 2021, in Florham Park, N.J. (Photo by Kathy Willens/AP Photo)