As humanity prepares to return to the Moon with the Artemis program, one critical challenge has emerged that most people never think about: what time is it on the Moon? On April 2, 2024, the White House Office of Science and Technology Policy (OSTP) directed NASA to establish a unified lunar time standard called Coordinated Lunar Time, or LTC, by the end of 2026.
Naha Bulan Peryogikeun Waktu Sorangan
On Earth, we rely on Coordinated Universal Time (UTC), which is maintained by a network of over 400 atomic clocks worldwide. GPS satellites, financial systems, power grids, and the internet all depend on precise synchronization with UTC.
The Moon presents a unique problem. Due to its weaker gravitational field, clocks on the lunar surface tick approximately 56.02 microseconds faster per Earth day than identical clocks on Earth. This effect — predicted by Einstein's general theory of relativity — means that a simple relay of Earth time to the Moon would slowly drift out of sync with local lunar clocks.
Over the course of a single day, 56 microseconds may seem negligible. But for navigation systems, that drift translates to position errors of about 16 meters per day. Over a month, errors would reach nearly 500 meters — enough to make precision landings, rover navigation, and communication relay timing unreliable.
Kumaha LTC Bakal Jalan
Coordinated Lunar Time bakal diadegkeun dina prinsip anu sarua jeung UTC tapi diadaptasikeun pikeun lingkungan lunar. Rencanana melibatkeun penempatan jaringan jam atomik di permukaan Bulan jeung dina orbit lunar. Jam ieu bakal digunakeun pikeun ngitung rata-rata bobotan anu nangtukeun waktu lunar resmi.
LTC bakal ngajaga hubungan tetap, anu didéfinisikaeun kalayan UTC jadi waktu bisa dikonvérsian ngampar antara Bumi jeung Bulan. Perbedaan konci nyaéta LTC bakal nyaanjangkeun offset relativistik — drift kumulatip anu ngarajeung jam lunar ngajalan leuwih gancang.
The National Institute of Standards and Technology (NIST) menerbitkeun technical framework dina Agustus 2024 ngajelaskeun model matematik pikeun niturunkeun waktu lunar tina koreksi relativistik ka UTC.
The International Effort
Lunar timekeeping is not just a NASA project. The United Nations International Committee on Global Navigation Satellite Systems (ICG) established a dedicated working group in 2024 to standardize lunar timing internationally. The Artemis Accords — signed by over 50 nations — recognize the need for interoperable systems, and a shared time reference is foundational to that goal.
The European Space Agency (ESA) has also been studying lunar timekeeping as part of its Moonlight initiative, which aims to provide communication and navigation services around the Moon.
Naon Maksudna LTC Pikeun Payun
A standardized lunar time will enable precision navigation for landers and rovers, reliable communication scheduling between Earth and the Moon, coordination between missions from different space agencies, and eventually a foundation for timekeeping on Mars and beyond.
The simulated Coordinated Lunar Time shown on moontimenow.com uses the published drift rate of +56.02 microseconds per day, accumulated from the J2000.0 epoch, to approximate what an official LTC clock would read today.