Hello and welcome to the Stellarium Wiki!
When translating pages, please don't overwrite the original English text, as you did with Help:Contents. I reverted it, but your text is still available in the history of the article here (don't click "Save page"!), so you can copy it to a more suitable location.
The problem with that particular page is that "Help" is a MediaWiki namespace, so "Помощь:Содержание" is not a direct equivalent (there's no namespace "Помощь"). Possible alternatives are Help:Содержание or Help:Contents/ru, with Помощь:Содержание redirecting to that page. Please choose one of the two variants and copy your text there. I can create the redirect, if necessary.--Daggerstab 06:21, 10 March 2011 (UTC)