An artwork entitled “Are you still mad at me?” by John Isaacs is displayed at the Death: A Self-portrait exhibition at the Wellcome Collection on November 14, 2012 in London, England. The exhibition showcases 300 works from a unique collection by Richard Harris, a former antique print dealer from Chicago, devoted to the iconography of death. The display highlights art works, historical artifacts, anatomical illustrations and ephemera from around the world and opens on November 15, 2012 until February 24, 2013. (Photo by Peter Macdiarmid)

President Barack Obama watches as Joey Hudy (L), 14, from Phoenix, Arizona pumps the Extreme Marshmallow Cannon he invented, while touring student science fair projects on exhibit in the State Dining Room at the White House February 7, 2012 in Washington, DC. Obama hosted the second White House Science Fair celebrating the student winners of science, technology, engineering and math (STEM) competitions from across the country. (Photo by Molly Riley-Pool/Getty Images)

A women rides a motor bike on a street covered with volcanic ash from an eruption of Mount Kelud, in Solo, Indonesia, Friday, February 14, 2014. A major volcanic eruption in Indonesia blasted clouds of ash and debris 18 kilometers (12 miles) into the air on Friday, forcing authorities to close six airports, cancel flights elsewhere in Southeast Asia and evacuate more than 100,000 people from the mountain. (Photo by Hafidz Novalsyah/AP Photo)

Mia Sanford, graduating from Dr. Michael M. Krop Senior High School, takes a selfie picture with friends before participating in a parade of vehicles celebrating the graduating 2020 High School seniors on May 14, 2020 in Aventura, Florida. The graduating seniors were cheered on as they drove through the city escorted by the Aventura Police Department, students and parents. The unorthodox graduation ceremony was created as a way to safely celebrate during the coronavirus pandemic. (Photo by Joe Raedle/Getty Images)

A man raises his fist as a group of Black Lives Matter marchers approached Brooklyn's Grand Army Plaza ast the beginning of a Caribbean-led rally, Sunday, June 14, 2020, in New York. Protests have grown since the May 25th death of George Floyd, a black man who died inn police custody in Minneapolis after a white police officer pressed his knee into Floyd's neck for nearly nine minutes. (Photo by Kathy Willens/AP Photo)

Sugar gliders, Candy and Popcorn, enjoy their favourite food, Nectar, at Wild Life Sydney Zoo on February 14, 2017 in Sydney, Australia. The treat made up of honey, high protein baby cereal and egg yolks is the human equivalent to chocolate to the Sugar Gliders. St. Valentine's Day or the Feast of Saint Valentine began as a celebration of the early Christian Saint Valentinus. From the 18th Century onwards it has steadily transformed into a celebration of romantic love and sentiment in many countries around the world. (Photo by James D. Morgan/Getty Images)

In this September 14, 2017 photo, young women pose for a photo inside their squatter building that used to house the Brazilian Institute of Geography and Statistics (IBGE) in the Mangueira slum of Rio de Janeiro, Brazil. Many lower-middle class Brazilians who gained ground during the boom years have since slid back closer to the poverty line. (Photo by Felipe Dana/AP Photo)

In this photo taken on Sunday, January 14, 2018, Anastasia Gruzdeva, left, poses for selfie with her friends as the temperature dropped to about –50 degrees (–58 degrees Fahrenheit) in Yakutsk, Russia. Temperatures in the remote, diamond-rich Russian region of Yakutia have dropped to near-record lows, plunging to –67 degrees Centigrade (-88.6 degrees Fahrenheit) in some areas. (Photo by Sakhalife.ru Photo via AP Photo)