Iran fired about 180 ballistic missiles in a massive aerial barrage on Israel on Tuesday – the majority of which were intercepted by Israeli air defences.
But some made it through multiple layers of surface-to-air missile systems that are in place to defend the Jewish state.
Footage circulating on social media appeared to show streaks of light smashing into the ground and the subsequent damage resulting from the strikes.
It prompted questions over whether Iran had successfully defeated one of the world’s most robust air-defence systems.
While analysts have cautioned that it’s too early to tell, there are a few telltale signs to look out for when assessing the system’s performance.
Timing
When Iran last launched an attack on Israel in April, the strike was telegraphed so far ahead that most of the world had a week to prepare.
Israel and its US, UK and European allies were given sufficient time to ready themselves to deploy fighter jets and warships to help take down the Iranian barrage of drones and missiles.
“This one was in relative terms more surprising,” Samuel Hickey, of the Center for Arms Control and Non-Proliferation, said.
More advanced weaponry
In Iran’s first large-scale attack on Israel, it used a combination of some 300 missiles and drones.
While the combined number is greater than the 200 fired late on Monday, the initial strike was made up mostly of cruise missiles and drones.
“It used slower cruise missiles and drones – suicide drones – that can be shot out of the sky by aircraft,” Mr Hickey said.
Ballistic missiles can fly at hypersonic speeds above mach-5 making them much harder to intercept by fighter jets or ground-based systems.
“Fighter jets are less likely to have been a huge factor,” Mr Hickey added.
Conserving ammunition
Air defence is a costly business.
It was estimated the April attack cost Israel and its allies around £1.1 billion ($1.5 billion) to head off the barrage.
There is also the problem that interceptor rockets are limited in numbers. Western efforts to help Ukraine defend its cities against Russian bombardments has used up significant resources in this area.
With both Israel and Ukraine largely reliant on the US for these interceptors, decisions have to be made.
“We still don’t know how many missiles Israel decided to engage, any number of missiles do just land in areas that aren’t going to cause much damage to human life or infrastructure… they will choose to let them pass” Mr Hickey said.
Decisions like this could help Israel conserve interceptor ammunition for further attacks on its territory.
Saturation
Again, because there are genuine concerns about the scarcity of air-defence interceptors, there are fears Iran could attempt to overwhelm Israel in any large-scale bombardment.
“Tonight it seems that Iran launched fewer but more advanced missiles, but if this was to escalate into a conflict, this is something Israel is probably aware of,” Mr Hickey said.
“That might be a reason not to escalate this into a full conflict.”
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