Months of painstaking setup and delicate experimentation paid off recently for Artyom Kossolapov with a thrilling moment of discovery. It came while the nuclear science and engineering student was conducting research for his master's degree, as he observed a metallic device immersed in water. “As we increased power, bubbles emerged that formed a film coating the metal surface, trapping heat and creating a hotspot—a big blob—and I realized I was watching the phenomenon of critical heat flux in real time,” recalls Kossolapov. “It was very exciting seeing this happen live; it felt like a big breakthrough.” Critical heat flux (CHF) poses a central problem for the field of nuclear engineering. The conditions underlying CHF occur in boiling water systems such as nuclear reactors when a dangerous combination of heat and pressure “creates so many bubbles that they clump together, forming a vapor film, which insulates the heated surface from cooling liquids and potentially creates dangerous instability,” explains Kossolapov.