Former U.S. Vice presidential candidate and Alaska Governor Sarah Palin (R) greets some of the thousands of motorcycle enthusiasts and military veterans participating in 'Rolling Thunder' rally May 29, 2011 in Arlington, Virginia. Although not an official guest, former U.S. Vice presidential candidate and Alaska governor Sarah Palin is expected to participate in today's motorcycle parade from the Pentagon to the National Mall.

New York Police Department tactical police officers stand guard near the New York Stock Exchange on September 9, 2011 in New York City. Officials are stepping up security in New York and Washington D.C. a day after U.S. officials received a credible but unconfirmed terror threat to utilize car bombs on bridges or tunnels in New York or Washington. (Photo by Justin Sullivan/Getty Images)

Bao Bao, the Giant Panda cub is seen by the media for the first time January 6, 2014 inside his glass enclosure at the Smithsonian's National Zoo in Washington, DC, a few days before going on display to the general public. Bao Bao was born at the Smithsonian's National Zoo August 2, 2013. (Photo by Paul J. Richards/AFP Photo)

A British space-exploration company has revealed its aim to fly the public to the moon from 2015 – providing they have £100m for a ticket.

Photo: Jenn Sander from Red Robin PR, wearing a spacesuit once worn by US Astronaut Peggy Whitson, sits inside a re-entry capsule owned by Excalibur Almaz outside the Queen Elizabeth II Centre on June 19, 2012 in London, England. The company today announced their plan to fly people to the moon on what is the 40th anniversary year of the Apollo 17 moon landing. (Photo by Rosie Hallam)

Activists protest the Shell Oil Company's drilling rig Polar Pioneer which is parked at Terminal 5 at the Port of Seattle, Washington May 16, 2015. Hundreds of activists in kayaks and small boats fanned out on a Seattle bay on Saturday to protest plans by Royal Dutch Shell to resume oil exploration in the Arctic and keep two of its drilling rigs stored in the city's port. (Photo by Jason Redmond/Reuters)

The Boeing 747-8 Intercontinental airliner, the company's newest and largest passenger plane, takes off for its first test flight at Paine Field Airport March 20, 2011 in Everett, Washington. The new plane features quieter, more fuel efficient engines, more seating and a redesigned interior.

Shipping containers sit idle at the ports of Los Angeles and Long Beach, California in this aerial photo taken February 6, 2015. The loading and unloading of cargo freighters has been suspended at all 29 U.S. West Coast ports this weekend because of chronic slowdowns on the docks that shippers and terminal operators have blamed on the dockworkers' union, the companies said Friday. (Photo by Bob Riha, Jr./Reuters)