lcogt.netは安全ですか？

I see no privacy policy on this site. However, it was bookmarked on Diigo twice since 2009 (as well as Delicious). It is a little non-traditional (privately-funded observatory network) but the content of the posts that I've read e.g. regarding linked data, are sensible and consistent with accepted standards. I'm not familiar enough with astronomy to comment on the reliability of that sort of site content. There is no obtrusive advertising. This is a child-safe site, and I rated it on that basis, and for trustworthiness.