Singers Steven Tyler (L) and Nicole Scherzinger perform onstage at the iHeartRadio Music Festival held at the MGM Grand Garden Arena on September 24, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for Clear Channel)

Ten-year-old Macy Friday, front left, reacts as she looks back at her family after meeting Hillary Clinton, front right, as she campaigns for U.S. Sen. Mark Udall, D-Colo., back, during a stop in the newly-renovated Union Station in Denver on Monday, October 13, 2014. Clinton appeared at an event to raise money for Udall's current re-election campaign and then headed to Las Vegas for another appearance on Monday night. (Photo by David Zalubowski/AP Photo)

An incredible view of Thunderstorms light up the insides of clouds near a beautiful sky line. This is truly heavenly weather as pictures taken from an airplane cockpit reveal what pilots see from above. It looks like at cruising altitude the weather really hots up, with the flight deck revealing some amazing scenes. Thunderstorms light up the insides of clouds, lightening streaks across the sky like cracks in a windscreen, the northern lights sweep uninterrupted across the sky and the galaxy stretches on forever. The pictures were captured by senior first officer Christiaan van Heijst, a 33-year-old from the Netherlands, and his friend Daan Krans. (Photo by Christiaan van Heijst/Daan Krans/Caters News Agency)

Enya Kim from the Natural History department at auctioneers Bonhams & Butterfields stands in front of one of the world's largest set of shark jaws comprised of about 180 fossil teeth from the prehistoric species, Carcharocles megalodon, which grew to the size of a school bus, at the Venetian Resort Hotel Casino September 30, 2009 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)

Dameon Harris of Nevada gets used to the controls of a bulldozer at Dig This October 27, 2011 in Las Vegas, Nevada. At Dig This, tourists take a short class and can then operate full-size hydraulic excavators and track-type bulldozers in a giant sandbox while being guided by instructors over headsets. (Photo by Ethan Miller/Getty Images)

A poster advertises the highly anticipated video game, “Call Of Duty: Modern Warfare 3” at a GameStop Corp. store November 6, 2011 in North Las Vegas, Nevada. Video game publisher Activision plans to release the eighth installment in the “Call of Duty” franchise at midnight on November 8. (Photo by Ethan Miller/Getty Images)

SI bodypaint model, soccer player Alex Morgan (L) attends SI Swimsuit On Location hosted by Haze Nightclub at the Aria Resort & Casino at CityCenter on February 15, 2012 in Las Vegas, Nevada. (Photo by Michael Loccisano/Getty Images for Sports Illustrated)

An unknown number of guns are being built with the mechanisms, causing problems for the police and ATF officials. Photo: An ATF agent holds a generic unfinished receiver, back, and one that has been manufactured, front, at an ATF field office in Washington, on May 06, 2014. The ATF is trying to crack down on the trade in the makeshift guns by targeting shops and individuals who offer to turn the unfinished receivers into functional pieces for firearms. (Photo by Bill O'Leary/The Washington Post)