Why does America want to create a lunar time zone?

The first thing to know is that time flows differently in different parts of the universe.

Just as gravity is not the same for everyone, there is no universal time common to all celestial bodies.

Compared to Earth, “the Moon's gravity is slightly weaker and the clocks work differently,” astronomer Catherine Heymans told BBC Radio 4's Today programme.

If these clocks were placed on the moon, they would run one second faster in 50 years.

Currently, time on Earth is measured by hundreds of atomic clocks installed around our planet, which record changes in the energy state of atoms down to the nanosecond.

NASA communications and navigation representative Kevin Goggins explains that in this context, “when you go to another body, like the Moon or Mars, it makes sense that each has its own heartbeat.”

The idea that time is relative comes from the theory of general relativityAlbert Einstein.

The premise is that where gravity is strongest, time moves very slowly.

As the mass of the object increases, the force of gravity becomes stronger.

For example, a container filled with a dense material such as granite has more mass and therefore exerts a stronger gravitational force than the same container filled with water.

Since the mass of the Moon in space is less than that of the Earth, the gravitational force of the Moon is less than that of the Earth.

This explains why a person weighs less on the moon.

This low gravity is responsible for the famous photographs taken by the Apollo astronauts on the surface of the Moon, the “one giant step for mankind”.

Thus, the greater the mass of a body, the stronger its gravity and the slower it passes.

For example, on Jupiter, time passes more slowly than on Earth, because gravity is stronger.

But on the Moon, because its gravity is weaker, time passes faster.

The White House has asked the US space agency (NASA) to create a new time zone for the moon. “Coordinated Lunar Time”.

This new time zone will help ensure that national and private efforts to reach the moon are not fragmented.

However, it is not easy for all countries to agree on the form this new time system should take and the international organization responsible for coordinating it.

Currently, this work is carried out by the International Bureau of Weights and Measures (BIPM) for terrestrial time.

This is where the “Unified Universal Time” Used by the International Space Station.

But in the space race centered on the Moon, the definition of time used by the International Space Station may not be the most appropriate, experts say.

Another element is that countries must agree on the start and end point of the new deadline.

Could rival countries like China, Russia and the US adopt the new “lunar time”?

This does not seem so simple in the context of geopolitical tensions in international relations.

The US wants its new lunar program ready by 2026, in time to send humans to the moon.

Artemis-3 will be the first mission to return to the lunar surface since Apollo 17 in 1972. It is expected to land on the moon's south pole, which is believed to contain large water ice in sunlit craters.

This task requires discovery and guidance Extreme precision, on the order of nanosecondsAny error of judgment could result in the spacecraft positioning themselves in the wrong orbit and causing a collision.

The lack of coordination of lunar time between countries planning to land on the satellite and private companies can create new problems, reducing the chances of mission success and disrupting the exchange of data and information between the spacecraft, satellites and Earth. .