By
Anna Lombardi
(La Repubblica)
The question asked by Arati Prabhakar, an engineer of Indian origin at the head of OSTP (the White House Office of Science and Technology Policy), is far from trivial: What time is it on the Moon? ? It charged NASA
with "establishing a time frame on and around celestial bodies other than Earth
. "
In other words, the goal is to define a lunar time zone by December 2026.
Due to the difference in gravity (the Moon has a mass equivalent to 27% of Earth's), time passes slightly faster there than on our planet. Indeed, it is ahead by 58.7 microseconds per day,
“with additional periodic variations
,” according to the White House memorandum dated Tuesday, April 2. This difference, although minimal (equivalent to 1 second every 50 years), could however complicate the synchronization of spaceships and future...