How deep is the ocean? How wide is the sea?
Neither as deep nor as wide as the world's many outdated nautical charts show.
Vast stretches of coastlines around the globe have never been accurately surveyed. The locations of many small islands hundreds of kilometers from mainlands are known only approximately.
Parts of New York Harbor, where 24,000 ships arrive and depart every year, are still charted with data collected in the 1800s, using primitive lead-weighted lines to determine depths.
Results of relying on outdated charts can range from the merely embarrassing, as when the British luxury liner Queen Elizabeth II bumped into some unnoted rocks off the coast of Massachusetts in August, to a potential full-blown disaster.
In 1989, a Japanese ship approaching a harbor on the southeast coast of Alaska struck an uncharted underwater peak 10 feet beneath the surface.
The last survey of those waters, taken by lead line in 1917, showed a depth of 66 feet. A new survey after the accident revealed several other pinnacles the lead-line soundings had missed.
The second-largest oil spill in Alaskan history occurred in 1987, when the oil tanker Glacier Bay struck a rock in an area of Alaska's Cook Inlet that was not precisely charted. The area's $50-million salmon fishery had to shut down.
A $100-million lawsuit brought by the shipping company against the National Oceanographic and Atmospheric Administration is still pending. NOAA has legal responsibility for producing accurate charts in the United States.
New technology that is expected to be in use in the next two or three years will make nautical charts more accurate and considerably easier to produce.
But because updating charts will still be expensive and time-consuming, experts think maritime accidents caused by faulty chart information will continue for a while.
"It's very definitely a problem," says Christian Andreasen, head of the Monaco-based International Hydrographic Bureau. "And it's not something you can do much about instantly."
Although most people now travel by air, cruise ships are increasingly popular.
The capacity of world cruise ships is growing at 11 percent annually and will increase 50 percent by 1994, based on ships now on order.
But a more immediate concern is shipping _ including hazardous cargoes such as petroleum. In the United States, 99.8 percent of all foreign trade by weight is carried by marine transportation.
Because of high operating costs, captains of tankers and other freight vessels are under constant pressure to reduce the time they are underway.
Some are tempted to stray from well-charted shipping lanes into poorly charted areas in search of shortcuts.
"If you don't give mariners good data, people are going to get into trouble and you're going to have an oil spill to contend with that costs billions of dollars once it happens," says Andreasen, who recently retired as deputy chief of operations for NOAA's uniformed corps.
NOAA officials have long complained that they lack the resources necessary to keep nautical charts reasonably updated.
During an investigation of the Queen Elizabeth II grounding, Capt. Donald Suloff, deputy director of NOAA's survey branch, testified that of the 90,000 miles of U.S. shoreline, at least half of it is charted on information that is at least 50 years old.
"It's basically a lack of resources," says another official, Lt. Cmdr. John Wilder of the NOAA geodetic survey department.