We can read this question in at least two ways, with potentially different answers.
First, we can imagine that this question means to ask whether science can tell us which actions are and are not moral. If this is what the question means, the answer must surely be "no." Science cannot determine for us which actions are moral and are not.
Second, we can imagine that the question is asking whether science can explain why we tend to want to act in ways that we think are moral. That seems to be what, for example, Post #3 is talking about. If that is the question, then science may some day be able to provide a foundation for morality.
In general, though, I would argue that scientific knowledge and knowledge of what is moral are two different things.