Videos showing the effectiveness of Israel's Iron Dome missile defense system against rockets from Gaza have been posted and watched hundreds of thousands of times on the internet. They show dozens of glowing bullets whirring through the air against the black night sky and lighting up brightly against a backdrop of sirens and explosions.

An Iron Dome battery consists of a radar unit and a control center that can detect projectiles soon after their launch and calculate their trajectory and target. It takes seconds for an approaching projectile to be detected. This is crucial because depending on how far they live from the Gaza Strip, people in Israel might only have 15 to 90 seconds to get to safety when the sirens start wailing.

A battery also has three or four rocket launchers with 20 missiles each should projectiles be headed toward populated areas. The interceptor missiles can be maneuvered in the air. However, they are not designed to strike an approaching projectile but to explode close by and destroy it in the process. Falling debris can, therefore, still cause considerable damage.

'Damage and casualties'

There are currently 10 mobile Iron Dome systems in use in Israel. According to their manufacturer, Rafael Advanced Defense Systems, which develops military and defense technologies for the Israeli Defense Forces (IDF), a single battery can protect a medium-sized city and intercept rockets fired from a maximum of 70 kilometers away. Experts calculate that 13 systems would be needed in order to defend the entire country.

Iron Dome is designed to intercept short-range rockets and is used to complement other systems that Israel also uses.

The head of the Israel Missile Defense Organization, Moshe Patel, said more than 2,400 projectiles had been intercepted in the 10 years through January.

According to Rafael Advanced Defense Systems, more than 2,500 had been intercepted — with a 90% success rate.

"Every rocket intercepted by the system would have hit a civilian populated area, potentially causing severe damage and casualties," according to the IDF website.

Hamas tests Dome

The IDF claims that more than 1,000 rockets have been fired on Israel since the beginning of the week but that 200 of them did not clear the border and landed within the Gaza Strip. The radical Islamist militant group Hamas seems to be relying on the strategy of firing a whole tirade of rockets in quick succession in order to test Iron Dome and bring it to its limits.

One missile is reported to cost about €66,000 ($80,000). This is one of the reasons why they are only launched when a projectile is heading towards a populated area.

The US helped fund the development of the Iron Dome system and has since bought two batteries itself.