Dinosaur Jr. have been back for a couple of years, and have no right being as good as they are. Surely bands that break up and get back together are supposed to have lost something, right? Well not J. Mascis, Lou Barlow, and Murph - who continue to rock it like it's 1989.
Check out their performance on Fallon. Jump to the last notch on the timeline and it will take you to their performance - it should load right up.