Accurate timekeeping has always been crucial to navigation on land or sea, and it remains so to this day. For example, one of the key features of GPS satellites circling the earth are super-accurate atomic clocks. A new, permanent exhibit at the National Air and Space Museum in Washington, D.C. draws the connection between time and navigation, and showcases key artifacts in the evolution of modern navigation.
The exhibit is also intended to show what a long and difficult road we've followed to get to our present state of smartphone and GPS ease of navigation. In the past, wars were won or lost, commerce succeeded or failed, and lives hung in the balance depending on the available navigation tools and the skill and resourcefulness of their users.
"Time and Navigation is an ambitious exhibit because it traces the development of very complicated technologies and makes us think about a subject we now take for granted," said Gen. J.R. "Jack" Dailey, director of the museum. "Today, the technology needed to accurately navigate is integrated into mobile computers and phones: hundreds of years of technological heritage tell your handheld device where you are in a seamless manner. This opens up new possibilities and challenging questions for the next generation of scientists and explorers who visit this exhibit to start thinking about."
The exhibit is organized into five sections, covering three centuries spanning land and sea navigation plus space navigation. The sections include sea, air, space, satellite, and every-day navigation. In the space exhibit, for example, it's fascinating to learn that astronauts on the Apollo missions used a modernized version of the sextant (navigation by star position), which has been in use for hundreds of years by seafarers.
Navigating at Sea simulates a walk through a 19th-century sailing vessel. Visitors learn how navigators relied on chronometers and measurements of celestial objects to determine location. This section includes a 1602 mariner’s astrolabe; a Ramsden sextant and dividing engine; several chronometers; a model of Galileo’s pendulum clock, plus the earliest sea-going marine chronometer made in the United States, produced by Bostonian William Cranch Bond during the War of 1812 (see photo).
Navigating in the Air tells the story of aviation pioneers, and how they dealt with the unique challenges of aviation, including low-visbility conditions.
Inventing Satellite Navigation "describes how traveling in space inspired plans to navigate from space," museum literature states. "Innovators found that time from precise clocks on satellites, transmitted by radio signals, could be used to determine location. The U.S. military combined several breakthroughs to create the Global Positioning System—GPS. Some of the artifacts in this section are the NIST-7 atomic clock that served as the U.S. time standard in the 1990s, the navigation system from the nuclear submarine U.S.S. Alabama, a satellite from the Transit system used for global navigation before GPS and a test satellite global navigation built at the Naval Research Laboratory."
Navigation for Everyone tells the story of navigation and GPS technology from the perspective of a fireman, farmer, and a student. This section includes a disassembled mobile phone with a diagram showing all its parts and depicts how hundreds of years of navigation technology are now in the palm of a user’s hand. It also features "Stanley," the robot car that won the 2005 Grand Challenge, a robot race sponsored by the Defense Advanced Research Projects Agency.
The actual artifacts on display are great examples, ranging from a GPS-guided missile, to a 16th-century star-guide to help tell time, to early chronometers, to early GPS technology. All well worth a visit when you're in the Washington, D.C. Mall area