What impacts do astronomers make on society?
A general understanding of the universe and how its many wonders, but also some specific information about life-threatening objects in space.
Astronomers tend to enrich and expand our understanding of how the universe came to be and the many wondrous things in it.
Some fields of study, can have very immediate and practical applications like tracking large asteroids that, if their orbits intersected Earth's, could cause catastrophic damage to us. NASA has a program to track the largest of these asteroid objects.