Coordinated Lunar Time (LTC) needed due to differing gravitational forces
Nasa is working to create a new standard of time for the Moon that will see clocks move faster than on Earth, according to a White House memo.
The US Office of Science and Technology Policy (OSTP) directed the US space agency to set up a moon-centric time reference system that accounts for its differing gravitational forces.
In a memo on Tuesday, OSTP chief Arati Prabhakar noted that Earth-based clocks would appear to lose 58.7 microseconds per Earth-day as a result of these factors.
Nasa has until 2026 to set up a unified time standard, which Ms Prabhakar referred to as Coordinated Lunar Time (LTC). It will then be used by astronauts, spacecraft and satellites that require highly accurate timekeeping.
Maybe a dumb question, but why couldn’t they just use UTC?
My understanding is that’s exactly the point. To make clocks on the Moon be synchronized with UTC and not drift over time. You can only do that by making the clocks physically tick at different rate. This is because of relativity - time itself on the Moon passes at slightly different rate than on Earth, so if your clock is precise enough, you need to compensate for it. Just like GPS satellites need to compensate for being in slightly lower gravity and going fast relative to stationary clocks on Earth’s surface. This isn’t any kind of illusion, this is how the universe really works. If you’ve seen the movie Interstellar, it’s basically the same effect they experienced on the planet orbiting a black hole, just a much less extreme case.
other people have given good answers to this question but i think it’s worth saying that this isn’t a dumb question. it took a lot of smart people and thousands of years to figure out that time passes at different speeds in different parts of the universe. it’s not intuitive at all.
