In the study of ethics there is a good deal of science involved.

This is a genuine declaration of ignorance: I know of no scientific work giving *answers* to moral questions. That doesn't mean there isn't any, so I'd be happy hear of them.

There is, however, quite a lot around the subject. For example, there is research analogous to experiments in psychology, where people are asked to make a moral decision (eg the trolley and fat man scenario) and various things are measured, such as how common each answer is. People are also asked to account for why they took the decision they did.   There are other experiments that look at MRI scans while such decisions are being made. These things are useful, but they don't actual give advice on how to answer the question being considered. There are also links back to free will here: it has been questioned if a decision is being taken at all.

Also of interest is a list at the back of 'The Blank Slate', which names several hundred (if memory works) moral rules that anthropology has claimed are common to every society studied. The list can be criticised, of course: it is not clear that 'having sexual intercourse with your mother' always means the same thing (see W. Clinton for advice). But leaving such quibbles aside, the list is extensive and does not have anything to do with any specific formal religion. Which is as you would expect: every atheist I know properly and quite rightly states you can have a moral code without religion.