Certainly science can do much to inform us about our place in the world, but once we are made aware of our connection to others and the cosmos it cannot go very far in informing our moral stance because, as a previous writer pointed out, relativism begins creeping in.

If we agree that morality can be defined as ‘promoting well being’ for example, then we can clearly assess as state as a fact that something is moral, immoral, or not moral. So defining what we mean by the word ‘moral’ is the first step to solving the problem.

Read the Moral Landscape - Sam Harris. Great reading.

People who tell themselves morality is subjective just don't want to be bothered to reason their way through the consequences of their actions.

"Morality is not that complicated." I agree.