The phrase "surprising discovery" refers to finding something that astonishes or catches us off guard in a way that we didn't expect or anticipate. It's an unexpected piece of information or fact that can amaze or surprise us. Full definition
They also reveal surprising discoveries about how animals think and feel. (scientificamerican.com)
One of the most surprising discoveries in recent years in the outer Solar System is that there are small moons which have oceans inside them. (americaspace.com)
What was your most surprising discovery when researching the novel? (bookbrowse.com)