Logic soundly shows us that that which is "objective" is fundamentally inseparable from the abstract theories/models we create about it. In other words, it's ultimately not true that we can't really know anything. Consider, for example, that even calling something "objective" is itself an abstract theory of what constitutes objective.
It is commonly understood that the word "objective" in scientific terms translates roughly to "as objective as we can get in this life". Since no better standard is available to us, it makes sense to work with what we've got and not get too fussed about it. Civilization will progress either way.
Science is predicated upon Empiricism, which is merely a theory of knowledge acquisition, i.e. that all we can possibly know is known through observational experience.
Sounds lovely, but unfortunately this is a purely philosophical assumption and is empirically unfalsifiable. In other words, Science doesn't even have the capacity to explore and conclude upon its own assumptions. However, Philosophy does, and this very assumption was logically falsified thousands of years ago. The only reason Science works is because it defers to Philosophy and an understanding of the limits of inductive reasoning in order to control for observer participation, i.e. it gains the ability to dismiss any effect an observer may have upon that which he observes, but must concede comprehensive explanation as part of the bargain.
In other words, yes, there is a better standard. It's called logic.