Time-domain astronomy has experienced a renaissance during this recent decade. This field encompasses explosive transients, variable sources, and moving objects. The main goal of our observational research group at HUJI is the observational study of many types of cosmic explosions. While we study them in various wavelengths (including optical and Xray) our focus is on exploring them in radio waves (since radio observations provide unique diagnostics as they trace high-energy particles and magnetic fields), using several large telescopes around the world.