Ever look a statement like this and wonder "What does putting a 220 kg payload into a 500 km orbit mean if the rocket were used as a ballistic missile? Like, how far could it throw a nuclear weapon?" 1/7 https://twitter.com/KhosroKalbasi/status/1352351681036611584

Of course you do! To find the answer, you oughtt to make a detailed model by measuring the missile, estimating its parameters, and simulating its performance. Sadly, there often isn't enough information to do that properly. Garbage in, garbage out. 2/7

So, here is a fun thing we did at CNS -- we updated Steve Fetter's spreadsheet to turn information about space launchers (payload and orbit) into a range and payload estimate if that same rocket was used as a ballistic missile. 3/7

Now, this method is just an approximation. If you are curious about how to do it, Steve uses the method in his "Ballistic Missile Primer" to estimate the range-payload of Israel's Jericho II IRBM from its Shavit SLV. 4/7
https://fetter.it-prod-webhosting.aws.umd.edu/sites/default/files/fetter/files/1990-MissilePrimer.pdf

The method has a lot of limitations, but it can be very helpful when you don't know enough about the space launcher to properly model it. We validated it against some models of the Jericho II and III we made under a grant from @plough_shares. It does alright! 5/7

So, what's the answer for the Iranian SLVs?
* Zoljanah could send a 1,000 kg payload to ~4,000-5,000 km.
* Sarir would carry 1,000 kg to ~7,000-9,000 km.
These are just ballpark estimates, but they give you an idea of proliferation challenge raised by solid-propellant SLVs. 6/7

If you are interested in playing with Steve's spreadsheet and/or helping us improve it, my DMs are open. 7/7