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)

“An electronic cigarette, or e-cigarette, is an electrical device that simulates the act of tobacco smoking by producing an inhaled mist bearing the physical sensation, appearance, and often the flavor and nicotine content of inhaled tobacco smoke; though without its odor, and intended to omit its health risks. The device uses heat (or in some cases, ultrasonics) to vaporize a propylene glycol- or glycerin-based liquid solution into an aerosol mist, similar to the way a nebulizer or humidifier vaporizes solutions for inhalation”. – Wikipedia

Photo: Owner of a shop that sells electronic cigarettes demonstrates how to use one on March 1, 2012 in Berlin, Germany. The German government has announced that it classifies the liquids used in electronic cigarettes as pharmaceuticals because the liquids contain nicotine, and that sale of the liquids requires certification. (Photo Illustration by Sean Gallup/Getty Images)

Beneath the Swedish capital lies an intricate web of underground train lines. More than 90 of the 100 stations in the 110km tunnel system, sometimes referred to as “the world’s longest art gallery”, have been decorated with paintings, installations, mosaics and sculptures by 150 artists since the 1950s. After spending a couple of weeks exploring arctic Norway and Sweden, London-based travel photographer Conor MacNeill headed underground to capture images of the metro stations. Here: A rainbow arcs over a girl on the platform of Stadion station. (Photo by Conor MacNeill/The Observer)

(L-R) U.S. President Barack Obama, Queen Elizabeth II and First Lady Michelle Obama arrive at Winfield House, the residence of the Ambassador of the United States of America, in Regent's Park, on May 25, 2011 in London, England. The 44th President of the United States, Barack Obama, and First Lady Michelle are in the UK for a two day State Visit at the invitation of HM Queen Elizabeth II. Last night they attended a state banquet at Buckingham Palace and today's events include talks at Downing Street and the President will address both houses of Parliament at Westminster Hall. (Photo by Yui Mok - WPA Pool/Getty Images)

A woman walks past a painting by Jenny Saville entitled “Red Stare Head IV” on display in the Royal Academy of Arts' Summer Exhibition on June 2, 2011 in London, England. The Summer Exhibition is the world's largest open submission contemporary art show, now in its 243rd year, with over 12,000 entries received from 27 countries. The exhibition features over 1100 works of art including: painting, sculpture, photography, architecture and film, it officially opens to the public on June 7, 2011. (Photo by Oli Scarff/Getty Images)

“Felix Baumgartner (born 20 April 1969 in Salzburg, Austria) is a skydiver and a BASE jumper. He is renowned for the particularly dangerous nature of the stunts he has performed during his career. Baumgartner spent time in the Austrian military where he practiced parachute jumping, including training to land on small target zones”. – Wikipedia

Photo: Pilot Felix Baumgartner of Austria is seen before his jump during the first manned test flight for Red Bull Stratos on March 15, 2012 in Roswell, New Mexico. In this test he reach the altitude 21800 meters (71500 ft) and landed safely near Roswell. Red Bull Stratos is a mission to the edge of the earths atmosphere, where upon reaching altitude of 120,000 feet by helium baloon, pilot and basejumper Felix Baumgartner will then freefall to the ground in an attempt to break the speed of sound. (Photo by Jay Nemeth/Red Bull via Getty Images)

Kenny Wallace, driver of the #09 Family Farmers Toyota, spins into Justin Allgaier, driver of the #31 Brandt Chevrolet, who is lifted into the air by Reed Sorenson, driver of the #52 Means Racing Chevrolet, as Michael Annett, driver of the #43 Pilot Flying J. Ford, tries to avoid the wreckage during the NASCAR Nationwide Series DRIVE4COPD 300 at Daytona International Speedway on February 25, 2012 in Daytona Beach, Florida. (Photo by John Harrelson/Getty Images for NASCAR)

“The Great Barrier Reef is one of the most important sea turtle habitats in the world, with Lady Elliot Island being a key part of that habitat. Every year between November and March the green and loggerhead turtles lumber up the same beach on which they were born more than 50 years ago. These turtles nest on Lady Elliot Island up to nine times in a season, laying between 80 and 120 eggs per clutch. About eight weeks later, young hatchlings leave their nests and head towards the ocean (January to April)”. – Wikipedia

Photo: A Hawksbill sea turtle is seen swimming on January 15, 2012 in Lady Elliot Island, Australia. (Photo by Mark Kolbe/Getty Images)