As well described at the European ASPERA web site: "Astroparticle Physics is a new field of research emerging at the intersection of particle physics, astronomy, and cosmology. It aims to answer fundamental questions related to the story of the Universe such as: What is the Universe made of? What is the origin of cosmic rays? What is the nature of gravity?."

At UNM our programs include experiments studying the highest energy Cosmic Rays and the highest energy Gamma Rays and theory/phenomenology with the goal to better our understanding of the physics of "extreme universe" as found for example in Gamma Ray Bursts, Active Galactic Nuclei (aka super-massive black holes), and the environment near Pulsars.

As one example, the sources of the Ultra-High Energy Cosmic Rays are still a mystery 50 years after their first observation (by then UNM Adjunct Professor John Linsley).