The Bermuda Triangle is a patch of the Atlantic Ocean, out at sea between Florida, Puerto Rico and the island of Bermuda. For many years people have told stories and written books about it. NOAA, the U.S. ocean science agency, says there is no evidence that unexplained trouble happens more often in the Bermuda Triangle than in other busy parts of the ocean. The area people call the Bermuda Triangle covers about 500,000 square miles (1.3 million square kilometers) of ocean, and many ships and planes travel through it, so it is a busy part of the ocean. If the sea is not stranger than other seas, the next question is what it is like. The weather is a good place to look first.

According to NOAA, most Atlantic tropical storms and hurricanes pass through the Bermuda Triangle area. A hurricane is a big storm with strong winds that forms over warm ocean water. A storm is called a hurricane when its winds reach 74 miles per hour. Atlantic hurricane season runs from June 1 to November 30.

Before weather forecasts got better, ships in the area had less warning about storms than ships have today. The first weather satellite was launched in 1960. NASA launched TIROS-1, the world's first successful weather satellite, on April 1, 1960. It gave forecasters their first view of cloud formations around the globe.

The Gulf Stream is a stream of warm water that moves through the Atlantic Ocean. It carries warm water north along the coast of Florida and then across the Atlantic Ocean. It is sometimes 15 to 20 degrees Fahrenheit warmer than the water next to it. It has existed for only about 2.5 million years.

The Gulf Stream is fast as well as warm. It flows at about 4 miles per hour on average, and up to about 5.6 mph near the surface. It carries more water than all of the world's rivers combined. NOAA says the Gulf Stream can cause rapid, sometimes violent changes in weather.

Two more facts about water. The Caribbean has many islands, and they make wide areas of shallow water that can be hard for big ships to steer through. Rogue waves are unusually large waves that appear among smaller ones. They are more than twice the height of the surrounding waves, often from an unexpected direction.

Storms and currents are only half of the story. The other half is how the legend spread. It has a trail. The trail runs from a 1950 Associated Press story about five missing Navy planes, to a 1952 Fate magazine article called 'Sea Mystery at Our Back Door', to the name 'Bermuda Triangle' in Argosy magazine in February 1964. A 1974 book by Charles Berlitz became a best seller and made the Bermuda Triangle famous. A 1974 documentary, 'The Devil's Triangle', and Steven Spielberg's 1977 film 'Close Encounters of the Third Kind' helped spread the story.

In the 1970s a librarian named Larry Kusche checked the original records behind the Bermuda Triangle stories instead of just retelling them. His book 'The Bermuda Triangle Mystery—Solved' (Harper & Row, 1975) found that many accounts of vanishings were based on inaccurate information or careless research. He found that ships said to be lost in calm weather had actually met storms. For some missing vessels, wreckage was later found miles away, a fact the stories left out. Records kept by the Aviation Safety Network and the U.S. Coast Guard link many of the reported disappearances to storms or to unsafe conditions on the ships and planes themselves. Kusche found that some of the incidents in the stories happened far outside the Bermuda Triangle, and some did not happen at all.

In December 1945 a flight of five Navy training planes, known as Flight 19, lost track of where it was over the Atlantic off Florida. Its leader reported that the compasses seemed to be malfunctioning. In the 1940s nobody could watch storms from space, and ships and planes found their way with compasses, charts, dead reckoning and radio direction finders.

Two more groups have looked at the numbers. Lloyd's of London is the ship insurance company. According to EBSCO's research summary, Lloyd's of London and the U.S. Coast Guard both say this part of the Atlantic is not unusually dangerous, and that the number of accidents is in proportion to how busy the shipping route is. The Coast Guard has also said that a review of many aircraft and vessel losses in the area found nothing that indicated anything other than physical causes.

Words to know

• forecasts: weather predictions
• satellite: orbiting spacecraft
• shallow: not deep
• rogue: unexpected