What is Israel's Iron Dome missile defense system?

Since Israel activated the Iron Dome in 2011, the cutting-edge rocket-defense system has intercepted thousands of rockets fired into Israel, most from the Gaza Strip.

On Tuesday, it appeared the defense system was being used to intercept missiles coming in from Iran.

The system has given residents a sense of security, and Israelis can often be seen watching the projectiles flying through the skies and destroying their targets overhead.

Here is a look at the accomplishments — and limitations — of the Iron Dome.

How does the Iron Dome work?

The Iron Dome is a series of batteries that use radars to detect incoming short-range rockets and intercept them.

Each battery has three or four launchers, 20 missiles, and a radar, according to Raytheon, the U.S. defense giant that co-produces the system with Israel's Rafael Defense Systems.

Once the radar detects a rocket, the system determines whether the rocket is headed toward a populated area.

If so, it launches a missile to intercept and destroy the rocket. If the system determines the rocket is headed to an open area or into the sea, it is allowed to land, thus conserving missiles. According to the military, all interceptions occur in Israeli airspace.

The military has declined to comment on how many Iron Dome batteries are currently deployed. But as of 2021, Israel had 10 batteries scattered around the country, each able to defend a territory of 60 square miles (155 square kilometers), according to Raytheon.

The Iron Dome is part of a larger multi-layer air-defense system that includes the Arrow, which intercepts long-range ballistic missiles, and also David's Sling, which intercepts medium-range missiles such as those believed to be possessed by Hezbollah in Lebanon.

Both systems, like the Iron Dome, were jointly developed with the United States. Israel is also developing a laser-based system called the Iron Beam that it says will be able to intercept rockets and other short-range threats at a fraction of the cost of the Iron Dome. As of late last year, Israel said that system, developed with U.S. funding, had not yet been deployed.

How accurate is the Iron Dome?

It is roughly 90% effective, according to Rafael.

But it can get overwhelmed if a mass barrage of rockets is fired, allowing some to slip through.

Each missile costs an estimated $40,000 to $50,000, according to the Institute for National Security Studies, a Tel Aviv think tank.

The U.S. has invested heavily in the system, helping with development costs and replenishing it during times of fighting.

What else is behind Israel’s multilayered air-defense system?

Israel's defense system also includes the Arrow, which was developed with the U.S. and is designed to intercept long-range missiles, including the types of ballistic missiles Iran said it launched on Tuesday. The Arrow, which operates outside the atmosphere, has been used in the current war to intercept long-range missiles launched by Houthi militants in Yemen.

Another system is the David’s Sling, which was also developed with the U.S. and meant to intercept medium-range missiles, such as those possessed by Hezbollah in Lebanon.

The American-made Patriot system is the oldest member of Israel’s missile-defense system – used during the First Gulf War in 1991 to intercept Scud missiles fired by Iraq’s leader at the time, Saddam Hussein. The Patriot is now used to shoot down aircraft, including drones.

Due to the limitations of the Iron Dome, Israel has been developing a new system called the Iron Beam to intercept incoming threats with laser technology. Israel has said this system will be a game changer because it is much cheaper to operate than existing systems. However, it is not yet operational. Earlier this year, President Joe Biden signed a bill into law that includes $1.2 billion for the procurement of the the Iron Beam.