As the article makes clear it does more than just detect nuclear weapons though. It can be used to detect Conventional Weapons as well. Seems like a valid military Target to me. And frankly if Russia doesn’t like it they could always go home and stop this immediately, so hard to have any sympathy whatsoever for them.
Why even bother with the premise of whether it’s a valid military target or not? Russian attacks don’t discriminate based on that. Equal retaliation would mean that Ukraine could invade Russian territory and attack civilians in Russian cities, but they don’t because Ukraine is a nation of decent folk.
All sucks sites are legitimate military targets by definition - regardless of whether they have anything to do with conventional weapons. MAD is not about ethnics. MAD is about MAD. No one will give a damn whether there were also some pee shooters in the missle silo the destruction of which caused Armageddon. You don’t need sympathy. This brings you one step closer to disaster too.