Tomahawk missiles are highly accurate weapons. The modern version was first used by the United States in the 1991 Gulf War.

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Here’s what you need to know about Tomahawk missiles:

What are they?

Tomahawk missiles are subsonic, jet engine-powered missiles. They fly low, about 100 feet off the ground.

Where are they launched from?

Tomahawks can be launched from many surfaces, but the U.S. generally uses ships or submarines to launch the missiles.

How much do they cost?

Each missile cost $1.41 million.

Who makes them?

Raytheon Systems Company makes the Tomahawk Block IV.

How fast can they fly?

The missiles travel at 550 miles per hour.

How big are they?

The Tomahawk is a 20-foot-long missile, and weighs 2,900 pounds. It has a wingspan of eight feet,  nine inches. It carries a 1,000-pound-class warhead.

How accurate are they?

According to the Navy, they hit their target about 85 percent of the time. 

How do they find their target?

The missile uses a system called "Terrain Contour Matching." An altimeter along with an inertia detector direct the Tomahawk along a flight path against a pre-loaded map of the terrain. They are unlike drones as they are not guided by pilots on the ground. According to Raytheon, “The latest variant (Tomahawk Block IV) includes a two-way satellite data-link that enables the missile to be retargeted in flight to preprogrammed, alternate targets. The Block IV design was initiated as both a cost savings and a capability improvement effort.”

Is the United States the only country with cruise missiles?

No. More than 70 nations have cruise missiles.

Sources: The U.S. Navy; Popular Science; Raytheon