What we know about the US bunker-buster bombs that reportedly hit Iran's nuke sites

President Donald Trump said on Saturday that US military aircraft had struck Iranian nuclear sites.
The bombings targeted sites at Fordow, Natanz, and Esfahan.
The US reportedly used multiple GBU-57 Massive Ordnance Penetrator bunker-buster bombs in the operation.
The US's "massive precision strikes" on three Iranian nuclear facilities reportedly saw its forces unleash the GBU-57 Massive Ordnance Penetrator bunker-buster bomb.
Fox News host Sean Hannity said President Donald Trump had told him US forces used six bunker busters in strikes on Iran's Fordow site and 30 Tomahawk missiles in attacks on facilities at Natanz and Esfahan.
The GBU-57, designed to penetrate hardened bunkers, particularly those located deep underground, is among the heaviest and most powerful non-nuclear bombs in the US arsenal. It had never seen combat before the strikes against Iran's nuclear facilities.
Here's what we know about them.
The GBU-57 is a roughly 30,000-pound bomb that can only be carried by the B-2 Spirit bomber. It is around 20.5 feet long and has a diameter of 31.5 inches.
According to the US Air Force, the bomb is designed to target "weapons of mass destruction located in well protected facilities" and can penetrate up to 200 feet below ground before exploding.
Iran's Fordow facility is thought to be a key site for Tehran's nuclear enrichment activities, but its location — buried deep under a mountain — means Israel likely lacks the firepower to take out Fordow on its own, according to Heather Williams, a senior fellow in the Defense and Security Department at the Center for Strategic and International Studies.
Multiple hits by a GBU-57, however, could destroy it, she said.
Trump, who said a "full payload" of bombs had been used to strike Fordow, praised US forces for what he called a "very successful attack."
Trump called for peace in the aftermath of the strikes on the nuclear sites.
The attacks, however, are a significant escalation in the ongoing conflict. Earlier this month, Israel launched an intense air campaign against Iran aimed at degrading its nuclear capabilities. Tehran, which has said its nuclear program is for civilian purposes, has retaliated against Israel with heavy missile and drone strikes.
Trump said earlier this week that he was considering US involvement and indicated he'd take two weeks to mull over decisions to bomb Iran's nuclear facilities. He appears to have determined that less time was necessary.
Iran had threatened to retaliate against the US and its forces in the Middle East if it got involved in the Israel-Iran conflict. The US armed forces have a substantial force presence in the volatile region that the Department of Defense has said is intended to protect and defend American interests.

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