Sci fi daydream here.<p>What would it take for us to actually try to make such a signal ourselves in space? Really huge explosions? I suppose one weird way to see if they could be alien signals is see if we can imitate them.<p>Of course, that would be no guarantee that we aren’t just making bird calls imitating the sounds of car alarms (or other birds for that matter). But, I mean, if we can detect these signals, if we could generate one, maybe some other civilization would too. And if we proved that any civilization of a certain state could use the same technique, it would at least lend more probability to the possibility that these are something not natural phenomena.<p>And who knows, when the alien armada invasion force shows up, you’d know for sure it worked! Ah, such reckless abandon.