Here's a stab at your question: what is right is not only a function of the action and/or its consequences; it also depends on your values. Humans are not inherently valuable. The universe as a whole doesn't care about them, or about anything. But humans care about other humans. You probably care about humans. Thus the word "right", as it applies to you, means in part doing what's good for humans. If you only valued paperclips, then it would be right with respect to you for you to maximize paperclips at the cost of human lives--but it would still be wrong with respect to me and my preferences.

Some further resources: The sequence that will answer your question is the metaethics sequence. Any other questions you have can be posted in this month's open thread.