When the Nobel prize or Fields Medal gets awarded, I believe one of the criteria is the impact the discoveries have been. My question is, whether there are any objective ways to measure the impact? It could be the impact on science or on the society as a whole. I guess the number of citations or which journals have published an article is one way, but are there other ways? Can the objective ways be applied to compare between different fields of science? Are there any such comparisons where I could get a list of the most significant scientific discoveries ordered by impact?
Here is a related question: Quantitative measures of rise and decline of scientific fields over time (beyond number of publications)