http://hnrankings.info/7609667/
Dropping suddenly from 3rd to 20th on the front page suggests some sort of penalty being applied, but is it community driven, or automated? Even with the new openness about the actions of the moderators on HN I still find some things deeply confusing.
Added in edit: This does bring home just how important upvotes are. I've seen how disproportional the effect is of downvotes on an item's ranking - one downvotes out-weights many upvotes. If you like something, upvote it, or see it sink without trace.
Edit: We took the penalty off several hours ago: https://news.ycombinator.com/item?id=7611240
Certainly I thought the discussion was interesting.
FWIW, it's not me who has down-voted you. Not least, of course, I can't since your comment is a reply to mine. Personally I think your comment should not be down-voted - it's certainly of value.
We have no way of knowing which of these posts are particularly significant. Many people seem to upvote anything with SpaceX in the title, and I'm skeptical that it should be on the front page so often. Since you say this one is unusual, I believe you.
But really, please send questions like this to hn@ycombinator.com rather than posting them in the threads.
p.s. Downvoting that comment is fine; it's an efficient way for users to communicate that I made a mistake there. That's better than posting a low signal-noise reply.
Google/Facebook/Twitter are on the front page all the time, every time they make some little burp. I like those companies and what they do, but SpaceX is 1000x more interesting to me than any of those.