Pen and his team – including CITA post-doc Richard Shaw, U of T summer students Anita Bahmanyar, Natalie Price-Jones and Philip Isaac, Dunlap Institute Professor Keith Vanderlinde, and DAA Professor Marten van Kerwijk on the most recent observing run – is employing the Algonquin Radio Observatory, a 46-metre radio antenna built deep in Algonquin Park beginning in 1959, and a technique the ARO helped pioneer, Very Long Baseline Interferometry. VLBI is the use of radio telescopes at long distances from each other to represent a gathering area or dish as big as the separation between them. The telescopes are synchronized using the most accurate clocks available to simultaneously gather data of an object. The data is then combined using computer power and custom-written software.