Discussion about time on the earth satellite: timeless on the moon

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Lunar eclipse in November 2022: What time is it on the moon?

Photo: IMAGO/Vitaliy Ankov / IMAGO/SNA

A coffee date at 3:30 p.m. on the moon.

Such a meeting could not take place at the moment - not only because coffee is not being served there at the moment.

But also because there is no official moon time.

However, expeditions and the colonization of the celestial body in the coming decade will depend on a common time in order to be able to orientate oneself and cooperate better.

According to an article in the journal »Nature«, scientists around the world are discussing how the clocks on the moon should tick in the future.

International researchers therefore met in November in the Netherlands to exchange solutions to the topic.

They must come to an agreement in the coming years to prevent time chaos on the moon.

Important for communication

So far, moon expeditions have been based on the coordinated world time UTC, but have not been synchronized with each other.

With a previously manageable number of spaceships and missions on and around the moon, this did not pose a major problem. With the planned construction of permanent bases on the satellite, which will lead to a significant increase in people and vehicles there, a new one is needed Approach.

Scientists like Jörg Hahn, an expert at the European Space Agency Esa, therefore see the need for a common moon time in order to make cooperation and communication possible: "All of this has to be traced back to a kind of time reference, otherwise chaos reigns and things don't fit together," says Hahn to »Nature«.

This is particularly important in order to be able to determine positions on the moon using a GPS-like technology.

The coordinates of a person or a vehicle are displayed in conjunction with three satellites.

The time it takes for the signals from each of the satellites to reach that point gives the position.

The basic requirement for this is a universally valid time.

Clocks tick faster on the moon

On the moon, however, there are some pitfalls: according to the theory of relativity, the clocks tick a little faster there.

Because the moon has a weaker gravitational field than Earth, NASA scientist Cheryl Gramling estimates that time there runs 56 microseconds – or 56 millionths of a second – faster per 24 hours.

And even that tiny shift can make a big difference when it comes to location and communication.

On this basis, there are several ways to determine the new moon time: The time measured by several atomic clocks on the celestial body could be adjusted to the coordinated universal time at regular intervals, so that the earth and moon are synchronized.

But it would also be possible to let the slightly faster running time on the moon continue independently and to show the growing difference to coordinated universal time.

According to »Nature«, independent times could make sense, especially with a view to the future colonization of other celestial bodies, for which a temporal synchronization with Earth would be logistically more difficult.

Another question that arises is whether regions of the moon should be divided into different time zones like on Earth.

In any case, it is likely that the 24-hour system on Earth will also remain important for people in space, the reason being, among other things, the natural sleep rhythm – on the moon it lasts an average of 29.5 days from noon to noon.

ani/dpa