Significance of the Targeted Nuclear Scientists in the 12-Day War
The June 2025 war between Israel and Iran, called the 12-Day War, saw the death of many Iranian nuclear scientists who participated in or are linked to Iran’s nuclear weapons program. The Israel Defense Forces (IDF) has listed the names of eleven nuclear scientists that were eliminated during a series of attacks on the opening night of the war and afterwards. Media reporting has identified several other scientists who died during the war, bringing the total to almost 20 scientists. In addition, many family members were killed in the attacks. This study identified a total of 19 persons, eleven on the IDF list of Iranian scientists killed and another eight listed in Iranian media.
Post-Attack Assessment of Shahid Meysami Research Center
The Times of Israel reported that the site was believed to house “plastic explosives and advanced materials used in nuclear detonation testing." Iran’s detonation system, or multi-point initiators (shock wave generators) require highly purified plastic explosives in its channels.
Post-Attack Assessment of the First 12 Days of Israeli and U.S. Strikes on Iranian Nuclear Facilities
Israel’s historic Operation Rising Lion and the United States Operation Midnight Hammer have targeted many Iranian nuclear sites, causing massive damage to its nuclear program and setting it back significantly. After 12 days of military operations, a survey of the resulting damage is appropriate.
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Significance of the Targeted Nuclear Scientists in the 12-Day War
The June 2025 war between Israel and Iran, called the 12-Day War, saw the death of many Iranian nuclear scientists who participated in or are linked to Iran’s nuclear weapons program. The Israel Defense Forces (IDF) has listed the names of eleven nuclear scientists that were eliminated during a series of attacks on the opening night of the war and afterwards. Media reporting has identified several other scientists who died during the war, bringing the total to almost 20 scientists. In addition, many family members were killed in the attacks. This study identified a total of 19 persons, eleven on the IDF list of Iranian scientists killed and another eight listed in Iranian media.
Post-Attack Assessment of Shahid Meysami Research Center
The Times of Israel reported that the site was believed to house “plastic explosives and advanced materials used in nuclear detonation testing." Iran’s detonation system, or multi-point initiators (shock wave generators) require highly purified plastic explosives in its channels.
Post-Attack Assessment of the First 12 Days of Israeli and U.S. Strikes on Iranian Nuclear Facilities
Israel’s historic Operation Rising Lion and the United States Operation Midnight Hammer have targeted many Iranian nuclear sites, causing massive damage to its nuclear program and setting it back significantly. After 12 days of military operations, a survey...
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Satellite imagery taken by @Maxar today show ongoing work at the MOP impact points of the Fordow Enrichment Plant and progress in clearing access to the eastern tunnel entrance portal. As of July 1, Iran has sufficiently cleared the surroundings of the eastern tunnel portal to gain vehicle access to the entrance portal, although the extent of access inside the tunnel is unclear. At this eastern tunnel entrance portal, the entrance building had been destroyed and a bomb crater was previously visible above the tunnel entrance. Dump trucks likely used for hauling away debris were still visible yesterday.
At ventilation shaft #2 (per DOD schematic), Iran has used the large crane to offload the materials necessary to provide temporary cover over the shafts and erect a safety barrier (the crane boom is up, with a clear shadow visible, and various materials are scattered around the shaft area).
Iran also created a new makeshift access road to ventilation shaft site #1 from the south perimeter road where various vehicles, including one possible transporter, are present. Newly as of today, the ventilation shaft #1 is also covered, however, it looks like this is a temporary fix. It appears that the bulldozer has pushed earthen material down over the edge of the large encompassing crater lip into the ventilation shaft holes previously created by the bombing. Given the lack of mechanized equipment tracking next to the holes and all of the other unidentified activity near the holes, it is possible that they just have temporarily covered the holes such that earthworks can be conducted around the shaft openings without material and personnel falling into the shafts in the hope that the shafts can be reworked at some point in the future. Another, albeit less likely possibility given the depth of the shafts, is that the holes have been backfilled.
Overall, ventilation is critical to any future underground operations, so if Iran were ever to try to renew operations they would have to rebuild the shafts and associated infrastructure along with any other repairs required post attack. The shafts could be rebuilt in their current positions, or new ventilation shafts could be constructed in a different configuration, although this may take significantly more time to accomplish.
Right now the site is likely just undergoing damage assessment, which will soon be followed by recovery operations to access any salvageable equipment and materials and depending on the extent of damage, possibly also cleanup and repair. We will continue to monitor the situation and gain more insights as time goes on.
Analysis by @DAVIDHALBRIGHT1, @SarahBurkhard, @SFnuclear, and the Good ISIS Team.
Link to full tweet with graphics here.