Ahnighito, also known as the Cape York Meteorite, is a scary-big, 4.5 billion-year-old piece of an asteroid that fell out of the sky and landed in Greenland about 10,000 years ago. Non-Greenlanders first heard about it in 1818, but it wasn't until 1894 that intrepid Arctic explorer Robert E. Peary actually located the meteorite. For some reason, he thought it would be a swell idea to take it back to the American Museum of Natural History in New York. Before Peary could get the meteorite onto a ship, he had to get it to the coast, and that required the construction of Greenland's first and only railroad. It took three years to get all that done and transport the meteorite to its present location, where it sits on a special display stand whose supports are anchored into the bedrock beneath the museum [sources: Fabricius, American Museum of Natural History].