That boom echoing over ABQ was some sort of super-secret test at Sandia Labs. We can't tell you what they're blowing up, because they won't tell us. It's all a secret. But you can't keep noise and smoke a secret, so Sandia will tell us that they're periodically blowing up something until around 9 p.m., and you might hear booms across Albuquerque, and you might see smoke.
Living here in Albuquerque my whole life, I have heard more sonic-booms and crap getting exploded then a lot of people hear in a life time. I must say that having our airport share active runways with the Air Force Base is really kinda cool, as you get to see some cool shit take off when you are waiting for your plane.