Robert E. Peary was a well-known adventurer and arctic explorer who in 1909 set out to reach the North Pole. When he returned from the expedition, he claimed to have reached the pole on April 7, 1909. This report made him into an international celebrity. Though some historians have expressed doubts that Peary did in fact reach the North Pole, three arguments provide strong support for the truth of Peary's claim.

First, the National Geographic Society put together a committee that was instructed to conduct a thorough investigation of Peary's records and equipment. At the end of the investigation, the committee concluded that Peary's accounts were consistent and persuasive and declared that he had indeed reached the North Pole.

Second, a recent expedition provides support for Peary's claim that he reached the North Pole in only 37 days after setting out from Ellesmere Island off the coast of Greenland. Skeptics used to argue that Peary could not have traveled that fast, since even modern snowmobiles take longer to cover the same distance. However, a British explorer named Tom Avery recently made the same trek in less than 37 days. In fact, Avery used the same kind of dogsled and the same number and breed of dogs as Peary had. Thus, Peary's claims are not impossible, and he very well might have been telling the truth.

Third, there are photographs taken by Peary that support his claim to have reached the North Pole. Measuring the shadows in Peary's photographs makes it possible to calculate the Sun's position in the sky. The Sun's position established from the photographs corresponds exactly to the Sun's position as it should have been at the North Pole on that day. This provides strong evidence that Peary reached the North Pole and took the photographs there.