Scientists are planning to construct a cutting-edge laser inside one of the moon’s coldest craters in order to enhance navigation for lunar landers and rovers. Ultrastable lasers are crucial for systems that require extreme precision in timing and navigation. These lasers operate by bouncing a beam between two mirrors within a cavity, maintaining stability by keeping the beam length constant. Typically, the mirrors are kept in a vacuum at very low temperatures to prevent expansion or contraction and to isolate the system from external vibrations.
The moon’s polar regions contain numerous craters that are permanently shadowed, never receiving direct sunlight due to the moon’s minimal tilt. As a result, these areas are incredibly cold, with temperatures dropping to around -253°C (-20 kelvin) during lunar winter. Jun Ye and his team at JILA in Boulder, Colorado, propose that these frigid, stable conditions make these craters ideal for housing an ultrastable laser with unparalleled precision compared to those on Earth.
The proposed laser device would be similar to optical cavities developed in JILA’s labs, featuring a silicon chamber with two mirrors. While Earth-based optical cavity lasers can only maintain coherence for a few seconds, the moon-based laser could potentially remain coherent for up to a minute. This extended coherence would enable the laser to serve as a reference point for various lunar activities, including timekeeping, satellite coordination, and even supporting operations on Earth due to the short travel time for light between the moon and Earth.
Implementing this lunar laser system will pose challenges, but the concept holds promise for enhancing future moon landings, according to Simeon Barber from the Open University in the UK. Recent missions to the lunar poles have faced difficulties with landing due to illumination conditions affecting vision-based systems. Utilizing a stable laser for positioning, navigation, and timing could increase the success rate of high-latitude landings and support a wide range of lunar activities.
In conclusion, the development of an ultrastable laser within a moon crater presents an innovative solution for advancing lunar exploration and enhancing the reliability of navigation systems for both lunar and Earth-based operations. This groundbreaking technology has the potential to revolutionize space exploration and pave the way for future missions to the moon and beyond.

