the easy answer is "fresh content" the search engines all love fresh content. so when you publish your article or site or hub page will be given more credit than it is really worth.
that is great normally it is 48 hours.
the next part of your question is a little harder. that is how to keep it up there.
you must get back links in to that hubpage/article. look up all the backlinks hubs and articles that you can and learn.
i have put a "google alert" on the key phrases that relate to my topics and then i go to the blogs that show up in those alerts and i post comments on those blogs (with my link - site address) to get back links.
as your links grow so will your position in the search results.
hope this helps.