I see your topic as [dead]. I don't know anything about moderation here but the HN allows me to vouch some topics, maybe because I have high enough karma and I have set showdead option. That means that some kind of a moderation system (probably automated or semi-automated one) marked your post as kind of bad and somebody needs to vouch it.
I do not want to vouch your post, because I do not want even to read anything tied to UFO events.