Astronomy on Tap Flagstaff | Scaling in the Local Universe, or Why Do We See So Many Galaxies Colliding?

Join Lowell Observatory and Mother Road Brewing Co. on July 29th at 6:30pm for Astronomy on Tap! Listen to fascinating science talks, play trivia to win out-of-this-world prizes, and of course, enjoy Mother Road brews on tap.

This month’s speaker is Kathy DeGioia Eastwood is Professor Emerita of Physics and Astronomy at NAU and a volunteer at Lowell Observatory who will be talking about galaxy collisions. You might have seen the Hubble telescope story this winter about the Bullseye Galaxy, where spectacular rings were produced in a galaxy by a much smaller galaxy shooting straight through its heart. Or you may have seen countless other images of galaxies colliding, because they are indeed countless. But do we ever see stars colliding? Not really, no, although clearly there are more stars than galaxies in the universe.

Douglas Adams once famously wrote that “Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is.” That is so true that it really is impossible for us to visualize just how big space really is. The best that we can do is to scale different objects down to something we are familiar with. In this talk we will discuss several different scales which will explain why stars virtually never collide, and why galaxies in the local universe very often collide.