Can objective morality exist in Atheism?

[objectivitees]

Sure it does. If the society you belong to does not condone it, it matters.

Which part of "ultimately" did you miss in my reply? I didn't say it did not matter to society, I said it "ultimately" does not matter.

If I subjectively think that killing babies is fine, the society I'm in has something different to say about it.

Yes, but neither view would be "ultimate".

This does not mean that there is an objective standard, it just means I'm only as moral as my subjective societal norms perceive me to be.

That's what I meant. You seem to keep switching sides. If morality is relative to "societal norms" it's not "ultimate". If it's not "ultimate" it does not matter who survives and who dies.