Missing a train or bus can be an everyday inconvenience, but missing transportation to return to Earth from the Moon presents a whole different level of complexity. In anticipation of a future in which lunar missions become more common, NASA is moving forward with plans to introduce a uniform time zone on the Moon. This new initiative, called Coordinated Lunar Time (TCL), aims to simplify coordination of future missions and efforts to establish a permanent lunar base.

While the idea of ​​creating a lunar time zone has been discussed in the past, NASA recently confirmed that it will work closely with the US government, commercial partners and international standards organizations to ensure time on the Moon is constantly tracked and shared. . “As the commercial space industry grows and nations become more active on the moon, there is a greater need for time standardization,” said Ben Ashman, an aerospace engineer on NASA's Astronautics and Communications (SCaN) team. “Shared definition of time is an important part of safe, resilient and sustainable operations.”

The development of the TCL is an important step towards facilitating future lunar missions and coordinating the activities of multiple entities, including governments and private companies, aspiring to explore the Moon independently or in partnership.

To measure time on the Moon, NASA scientists plan to use atomic clocks, just as they do on Earth. These clocks use the energy frequency necessary for electrons to change their state in certain types of atoms, allowing time to be measured with extraordinary precision. However, major challenges arise due to gravitational differences between the Earth and the Moon, and these differences mean that the duration of each second is not identical on the two celestial bodies.

The Moon's reduced gravity causes clocks on its surface to advance by about 56 microseconds per day compared to those on Earth. This small difference may seem irrelevant, but as Cheryl Gramling, NASA's chief navigation systems engineer, explains, “For something traveling at the speed of light, 56 microseconds is enough time to travel a distance of approximately 168 football fields.”

Furthermore, Gramling highlights the importance of compensating for this effect. “If someone were orbiting the Moon, an observer on Earth who doesn't compensate for the effects of relativity over the course of a single day would think that the astronaut orbiting the Moon would be about 168 football fields away from his actual location,” he adds. This indicates the urgent need to precisely synchronize time between the Earth and the Moon.

NASA scientists are working intensively to develop mathematical models that will overcome this challenge. The goal is to ensure that the clocks of the astronauts and control operators on Earth are as synchronized as possible. Once these issues are resolved, NASA is confident that the TCL system can be expanded to be useful throughout the solar system, not just the Moon. This technology will be essential for coordinating future missions to Mars and other regions of deep space, enabling access to Mars for, for example, interplanetary video calls.

The creation of TCL is a key component of Project Artemis, NASA's initiative that aims to establish the first long-term human presence on the Moon. This project is one of NASA's most ambitious missions and involves planning a lunar station that could serve the basis for future space explorations. The next astronaut mission to the moon is scheduled to take place in 2026, and will represent a historic moment as it will include the first woman and the first person of color to set foot on the moon.

NASA's efforts to establish uniform time on the Moon represent a critical advance in space exploration and the ability to coordinate and manage human extraterrestrial activities. With TCL, the space agency takes another step towards a future in which space exploration becomes a reality for various countries and sectors, paving the way for a new era of discovery and innovation.