A team of scientists is exploring ways to use dark craters at the lunar poles as sites for ultrastable lasers to aid in surface and near-lunar navigation. The group, led by Physicist Jun Ye, an expert on lasers and precision measurements, were discussing the types of instruments that Artemis astronauts could install and use during their time on the Moon. According to Ye, some ideas were pretty good, while others were not. “I thought, ‘let me throw out another crazy idea’ — except it turned out to be not so crazy after all,” Ye noted. After working with silicon resonant cavities for years, Ye and his colleagues at both the University of Colorado's Joint Institute for Laboratory Astrophysics (JILA) and the German national metrology institute. along with researchers from NASA's Jet Propulsion Laboratory, know what's needed, particularly for the lasers. They need to be stabilized against motion, which meant an ultrastable silicon cavity housing.…