Listening for the cosmic ‘dark ages,’ from the lunar far side

In this episode of Science Friday, host Ira Flato explores the ambitious Lucy Knight mission, a small radio telescope designed to be deployed on the lunar far side. Led by Anja Slosar from Brookhaven National Laboratory, the project aims to serve as a pathfinder for future low-frequency radio astronomy by testing the feasibility of observing the universe from the moon's shielded far side. The far side offers a unique advantage: it's naturally shielded from Earth's radio interference and solar noise, making it ideal for detecting faint signals from the early universe. While Lucy Knight itself won't detect the elusive 'Dark Ages' signal—the faint radiation from neutral hydrogen before the first stars formed—it will demonstrate that the lunar far side is a viable location for such observations. The mission is scheduled to launch aboard a CLIPS (Commercial Lunar Payload Services) lander, Blue Ghost 2, in late 2026, marking the first U.S. private-sector landing on the lunar far side and the first functioning radio telescope there. Despite technical challenges like surviving extreme lunar temperatures and limited data transmission via relay satellites, the project represents a bold step toward unlocking the universe's earliest chapters. The episode also delves into the personal journey of Slosar, who was unexpectedly invited to lead the mission despite it bypassing traditional peer-review processes. She reflects on the excitement and pressure of building a space mission with minimal bureaucracy, likening it to being a postdoc again. The mission’s simplicity and autonomy are both its strength and its challenge. Listeners are left with a sense of wonder about the potential for future interferometer arrays on the moon and the possibility of discovering new physics—like novel dark matter signals—hidden in the unexplored low-frequency radio spectrum. The episode underscores how small, agile projects can pave the way for transformative science.