[R]esearchers at the Max Planck Institute for the Structure and Dynamics of Matter are reporting "ultrabright" electron sources with sufficient brightness to literally light up atomic motions in real time—at a time scale of 100 femtoseconds, making these sources particularly relevant to chemistry because atomic motions occur in that window of time. After seeing the first atomic movies of phase transitions in bulk thin films using high-energy (100 kilovolt) electron bunches, the researchers wondered if they could achieve atomic resolution of surface reactions—occurring within the first few monolayers of materials—to gain a better understanding of surface catalysis. So they devised...