A deep understanding of the new exhibit “Time and Navigation: The Untold Story of Getting From Here to There,” begins with a basic premise: If you want to know where you are, then you need to know what time it is.
What follows includes breakdowns of longitude and latitude, vibrations of the cesium atom, and Einstein’s Theory of Relativity.
Luckily, you don’t need a deep understanding of science to appreciate the ambitious, long-term exhibit, a collaboration between the Smithsonian’s National Air and Space Museum and the National Museum of American History, which opened Friday. Just like you don’t need to know how a smartphone works in order to call your mom, or to use the GPS.
But it does help.
At the exhibition entrance, there’s a large wall clock featuring an airplane, a satellite and and a submarine that rise and whirr every 15 minutes. That simple premise behind “Time and Navigation” is always clear — in the Middle Ages, Western Europeans understood that it took 24 hours for the Earth to rotate 360 degrees of longitude, making an accurate clock essential to accurate navigation. A few feet inside, the clocks get a lot more complicated.
The 150-artifact exhibition is organized into five sections and covers 300 years of earth and space exploration. It moves chronologically, beginning with marine navigation, then air, then space, then satellite, then modern navigational tools in everyday use.
Open-sea exploration is thousands of years old, and as practiced by the Vikings and Polynesians, for example, was based on constant headings according to stars and winds and the number of days it took to move between earthly bodies. It made for navigation that was subjective and imprecise.
,The Italian astronomer Galileo knew that every hour of the day was equal to 15 degrees of longitude — and in the early 1600s he worked on a clock that could go to sea. European nations offered prizes to anyone who could solve what they called “The Longitude Problem.” The 1700s saw the invention of sea clocks, and the first U.S. seagoing chronometer — able to measure the time of a known fixed location — made by Bostonian William Bond is featured in the exhibit. An interactive display allows visitors to use a sextant, which measures the angle between heavenly objects and the horizon to determine the user’s position, to navigate using stars. Clever visitors may be able to determine that they are in the United States, though possibly not on the Mall.
When humans became airborne, they had to contend with greater speeds and greater dangers. “Airplanes and engines are reliable,” says Roger Connor, curator of aeronautics for the Air and Space Museum, “navigation is not.” The “Navigating the Air” section features the stories of navigators, part of the crew of commercial airplanes into the 1960s, and their tools. It features the exhibition’s largest artifact, the Lockheed Vega the Winnie Mae, which shattered the around-the-world record in 1931, but the era is mostly marked by decades of deadly plane crashes. The end of the section marks another breakthrough: clocks with tiny quartz crystals that led to development of Long Range Navigation, a terrestrial system based on radio signals, around World War II.
By this point, the technology is likely soaring over most visitors’ heads. (In an eerie parallel, they might be compelled to look at their watches and wonder where am I?) But everyone can spot frames of reference that feel vaguely familiar.
New developments are often premised on old models says, Carlene Stephens, curator of timekeeping at the Museum of American History. “The first cars look like carriages. The first airplanes look like boats.”
Stephens explains that by the time human beings are dividing seconds into a 100,000 parts or more, we’re ready for “Navigating in Space.” The section includes a sextant from an Apollo space mission, and a duplicate Mariner 10 spacecraft, the first spacecraft to reach Mercury.
Another time breakthrough leads us to a device many drivers have on their dashboards.
The discovery that time from satellite clocks, transmitted by radio signals, could be used to determine location helped the U.S. military create the Global Positioning System or GPS in 1973. Paul Ceruzzi, Air and Space Museum chairman of space history, points out that navigational breakthroughs always have military and civilian uses — the Air Force and the fisherman both need to know where they are.
In the texts of the “Navigation for Everyone” section, a Massachusetts firefighter who lost six colleagues in a 1999 warehouse fire talks about how new technologies will allow firefighters to keep track of each other in burning buildings.
The next level in navigation is explored through a robot car named Stanley, which navigated 132 miles of desert in 2005 — and maybe portends a safer, cleaner, congestion-free commute one day. And there are efforts to build a wristwatch-size atomic clock. Perhaps that will help visitors navigate the technology in “Time and Navigation,” or at least find their way to the cafeteria when they are done.
at the Smithsonian National Air and Space Museum, Sixth Street and Independence Ave. SW. 202-633-1000. www.airandspace.si.edu.