Passengers watch as The Waverley, the world's last remaining seagoing passenger paddle steamer arrives at Clevedon Pier on June 10, 2011 in Clevedon, England. Built in 1946, the trust which owns and operates the Waverley, is warning that this could be the last season for the vessel and is appealling for more public funding saying it is struggling to make ends meet in the current financial climate due in part to rising fuel costs. Restored in 1973 after service on Loch Long in Scotland, since 2003, Waverley has been listed in the British National Register of Historic Ships core collection as 'a vessel of pre-eminent national importance'. (Photo by Matt Cardy/Getty Images)

A picture composed by the French street artist JR is plastered to a wall under a highway as part of a community project called “Through A Mother's Eyes”, which involves members of the economically distressed neighborhood of Hunts Point in images taken by and of themselves on June 30, 2011 in New York City. JR, a recent TED prize winner, has staged similar projects around the world that look to transform high crime and impoverished neighborhoods into spaces for street art combined with the celebration of community. (Photo by Spencer Platt/Getty Images)

Members of the public continue to pay their respects at the scene of a hit and run following civil disturbances in the Winson Green area on August 12, 2011 in Birmingham, England. Police are continuing investigations after three people – reportedly trying to protect shops from rioting and looting in Dudley Road – were struck by a car and killed during rioting. Police have so far arrested over 1,000 people following rioting which erupted over a four-day period across the UK. (Photo by Jeff J Mitchell/Getty Images)

Workers prepare the roof of a house to get installed solar power modules for producing heat on October 15, 2011 in Wessling, Germany. Germany has and is continuing to invest heavily in solar energy, both in the public and private sectors. The German government introduced a feed-in tariff with its Renewable Energy Act in 2000 that guarantees homeowners a minimum rate for selling electricity from renewable energy sources into the nation's electricity grid. (Photo by Alexandra Beier/Getty Images)

A protester holds a sign in front of riot policemen during an anti-G20 demonstration through the streets of Nice on November 1, 2011 in Nice, France. Anti-G20 demonstrators are gathered in Nice ahead of the arrival of the world's top economic leaders for the G20 summit in Cannes on November 3rd and 4th. The leaders are expected to debate current issues surrounding the global financial system in the hope of fending off a global recession and finding an answer to the Eurozone crisis. (Photo by Christopher Furlong/Getty Images)

Shimmering clearest blue and stretching as far as the eye can see, this is one of Iceland's famed crystal ice caves. The giant solid waves look frozen in time but they are slowly moving along as part of the Vatnajokull Glacier – which stretches across eight per cent of the island. The images were captured in February 2014 by British photographer Rob Lott, 49. Photo: A wide view of Rob Lott in the crystal ice cave in the Vatnajokull Glacier, Iceland. (Photo by Rob Lott/Barcroft Media)

Macro or Micro? Scientists’ pictures baffle our sense of scale. It began when Stephen Young, a geography professor at Salem State University in Massachusetts, tricked his biologist colleague Paul Kelly into thinking a satellite image was one of his electron microscope scans. Can you guess whether they are close-up or very far away? (Photo by Paul Kelly)