NASA's next giant leap: Creating a time zone for the moon

President Biden has given NASA the task of developing a revolutionary method of timekeeping tailored to the moon’s unique environmental conditions. This endeavor aims to create a “moon-centric” time reference system.

The project marks a departure from traditional Earth-based time zones, adapting instead to the moon’s lesser gravitational pull.

This adaptation is necessary as time on the moon elapses slightly faster – by 58.7 microseconds each day – due to these gravitational differences.

A new time for a new world

The directive, issued by the White House, calls for collaboration between NASA, other U.S. agencies, and international bodies to engineer this novel timekeeping system.

Kevin Coggins, NASA’s lead for communications and navigation, highlighted the importance of this project.

“An atomic clock on the moon will tick at a different rate than a clock on Earth. It makes sense that when you go to another body, like the moon or Mars, each one gets its own heartbeat,” said Coggins.

The heartbeat of high-tech space exploration

This initiative reflects the evolving needs of space exploration. In the past, astronauts relied on conventional watches during lunar missions.

However, the precision required for modern GPS, satellite technologies, and complex computer and communication systems necessitates more accurate timekeeping.

“Those microseconds matter when high tech systems interact,” Coggins explained, underscoring the critical nature of this endeavor.

Universal time, universal challenge

The call for a unified lunar time system isn’t a recent development. Last year, the European Space Agency pushed for a standardized time reference. This initiative was prompted by the moon’s extended day length.

The moon’s day is about 29.5 Earth days. This period is also known as the synodic month and is roughly the same as the time it takes for the moon to orbit the Earth once.

The International Space Station will maintain its use of Coordinated Universal Time (UTC), attributed to its close proximity to Earth. However, determining the onset of “space time” presents a challenge that NASA is ready to address.

Subsequently, the agency must navigate the intricacies of time measurement. Time can fluctuate even on Earth, occasionally necessitating the addition of leap seconds.

Clocks without changes: Simplifying lunar time

Notably, the lunar time system will forgo the concept of daylight saving time, maintaining a consistent measure throughout the lunar year.

The White House has set ambitious deadlines for this project, seeking a preliminary plan by the end of this year and a final strategy by the end of 2026.

Countdown to a new era

As NASA plans for upcoming lunar expeditions, including an orbital mission in September 2025 followed by a landing the subsequent year, the development of a moon-specific time system is not just a scientific endeavor but a foundational step towards future interplanetary exploration.

This initiative marks a significant milestone in human spaceflight, preparing for a future where time itself extends beyond our Earthly constraints.

The length of a moon day

The moon’s rotation period and its orbit around Earth are in sync due to a phenomenon called tidal locking, which results in the same side of the moon always facing Earth. 

Over time, the moon’s day length – the time it takes to complete one rotation on its axis – is gradually getting longer. This change in day length is primarily due to the tidal forces between the Earth and the moon. 

As the Earth’s gravity pulls on the moon, it creates a bulge. Since the Earth rotates faster than the moon orbits it, the bulge tries to align itself ahead of the moon-Earth line.

This causes a transfer of angular momentum from the Earth to the moon, slowing down the Earth’s rotation while pushing the moon further away from the Earth at a rate of about 3.8 centimeters per year. 

Consequently, as the moon moves away, its orbital period – and thus its day length – increases. This process is incredibly slow, and the extension of the moon’s day length over a century is only a matter of milliseconds, but over astronomical timescales, it significantly affects the dynamics of the Earth-moon system.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–