This is the Sam Harris route to ignoring the difficulties with defining an objective morality (I assign it to him as he was, as far as I can tell, the most vocal and prominent early advocate of this position).
It's really easy to define an objective morality, actually. It's just really difficult to justify it. Here's an objective morality: that which takes humans further away from the center of the earth is good. That which takes them closer is bad. (So, obviously, we ought all live as high as we can on mountains, and treat
scuba diving as a grievous sin.)
There's no doubt that science is a wonderful tool for providing us with information about many things. That it would have a lot to say about well being of humans is unsurprising.
The problems come when you start asking why: why well-being instead of happiness? Why just humans? How can you quantify it in a way that is correct, not just easy / measurable? How do you combine scores from different humans?
Harris dodges the question, essentially saying, "Wait, wait, wait. There are easy cases--malaria unambiguously decreases human well-being, and science will tell us that!"
This also ignores the point. Yes, there are easy cases, and they're already easy without this supposed framework for morality. Almost nobody seriously advocates for letting malaria run rampant or for spreading it. But there are other common problems, like increasing wealth disparities or the conflict between economic growth and environmental degradation or whether it is noble or evil to publicize the plight of starving children in Africa where you simply must answer many of these why questions.
So, science is an awesome tool, and we can apply it to help us answer questions of morality, but it doesn't tell us that the metric should be "human well-being" any more than it tells us it should be "distance from the earth's core".
It does however, tell us some things about morality that we tend to ignore. For example:
If morality is to be about humans at all, and if existence is better than non-existence, your morality had better not ever recommend a course of action that leads to extinction of humans.
As evolved creatures, many of our strongest drives are there because they are (or were) necessary or helpful in an evolutionary context: love of family, desire for sex, dislike of being enslaved, etc.. Elevating one of these to exalted status while ignoring the others is even more likely to be emotionally unworkable than something more comprehensive because they're all there for a reason. (To be determined: if keeping the underlying reason in mind is usually enough, or if you must always keep all the special cases in mind.)
We're big enough boys and girls now, technologically, that we can royally mess up our sandbox. Treating morality as self-centered interactions between individuals without considering our wider impact misses what is now a very important impact of humans on other humans. (To be determined: should that also fall under morality, or should there be a second set of rules? If a second set, how do you adjudicate when morality and conservation give different answers?)
Because of this, the closest thing to a scientifically objective morality is something like this: things are good to the extent that they maximize the chances for indefinite survival of human life (if not possible, fall back to other life in proportion to how closely related it is); things are bad to the extent to that they jeopardize it.
And it's not fully objective, either; that's just the behavior that the universe rewards with continued existence. Nor is it clear that it's enough to build a comprehensive morality. But, from what I've seen, it's about as far as one can get when leaning on science alone.