Ground zero



The term ground zero (sometimes also known as surface zero as distinguished from zero point ) describes the point on the Earth's surface closest to a detonation. In the case of an explosion above the ground, ground zero refers to the point on the ground directly below the detonation (see hypocenter).

The term has often been associated with nuclear explosions and other large bombs, but is also used in relation to earthquakes, epidemics and other disasters to mark the point of the most severe damage or destruction. The term is often re-used for disasters that have a geographic or conceptual epicenter.

Trinity, Hiroshima, and Nagasaki
The origins of the term ground zero began with the Manhattan Project and the bombing of Japan. The Strategic Bombing Survey of the atomic attacks, released in June 1946, used the term liberally, defining it as: "For convenience, the term 'ground zero' will be used to designate the point on the ground directly beneath the point of detonation, or 'air zero.'" William Laurence, an embedded reporter with the Manhattan Project, reported that "Zero" was "the code name given to the spot chosen for the atomic bomb test" in 1945.

The Oxford English Dictionary, citing the use of the term in a 1946 New York Times report on the destroyed city of Hiroshima, defines ground zero as "that part of the ground situated immediately under an exploding bomb, especially an atomic one."

The term was military slang, used at the Trinity site where the weapon tower for the first nuclear weapon was at "point zero", and moved into general use very shortly after the end of World War II. At Hiroshima, the hypocenter of the attack was Shima Hospital.

The Pentagon


The Pentagon, the headquarters of the U.S. Department of Defense in Arlington, Virginia, was thought of as the most likely target of a nuclear missile strike during the Cold War. The open space in the center is informally known as ground zero, and a snack bar located at the center of this plaza was nicknamed "Cafe Ground Zero".

World Trade Center


Since 2001 in the United States, especially in the media, "Ground Zero" is generally understood to mean the site of the World Trade Center, which was destroyed in the September 11 attacks. The phrase was being applied to the World Trade Center site within hours after the towers collapsed. It appears that the first use of the term on a mainstream North American media outlet in reference to the September 11 attacks was at approximately 11:55 am when an eye witness who claimed to be a Fox News freelancer referred twice to ground zero. He may also have been the first person to suggest the cause of the collapse of the towers was due to "structural failure due to fires". At 4:41 p.m., in an interview with Peter Jennings on ABC News, attorney and survivor of the attacks Tom Humphreys (spelled "Humphries" on air) said, in reference to the collapse of the South Tower, that The tragedy is that the police and fire personnel that tried to help people out of that building were right at Ground Zero when that happened...

The next known reference occurred at 7:47 p.m. (EDT) on that day, when CBS News reporter Jim Axelrod said: Less than four miles behind me is where the Twin Towers stood this morning. But not tonight. Ground Zero, as it's being described, in today's terrorist attacks that have sent aftershocks rippling across the country.

The term "Ground Zero" was simultaneously used by NBC News reporter Rehema Ellis when her own report was aired on NBC at around the same time as Jim Axelrod's report on CBS News. She said: We're now just a block away from the World Trade Center and the closer we get to "ground zero" the harder it is to breathe and to see.

Rescue workers also used the phrase "The Pile", referring to the pile of rubble that was left after the buildings collapsed. Even years later, the term "Ground zero" has become a shorthand for the site, even after construction on the new One World Trade Center and the National September 11 Memorial & Museum were well under way. In advance of the 10th anniversary of the attacks, New York City mayor Michael Bloomberg urged that the "Ground zero" moniker be retired, saying, "... the time has come to call those 16 acres what they are: The World Trade Center and the National September 11th Memorial and Museum."