What time is it? The answer you give can be different, because you are in different Earth's time zones (时区). But how could you tell the time if you are not anywhere on Earth?
Scientists are now thinking of creating a lunar (月球的) time zone. They believe it would be better for astronauts to communicate by using Moon Time, as they travel to, from, and across the Moon. At the moment, astronauts are using time zones of their own countries. But there could be safety problems caused by the differences in time-telling.
____ Gravity (引力) influences how quickly or slowly time passes. Since gravity is weaker on the Moon, clocks run a bit faster there. After 24 hours, a lunar clock would be 56 microseconds ahead of a clock on Earth. Another point to consider is that a full day on Earth is about 24 hours between two sunsets. While on the Moon, it is nearly 709 hours, about 29.5 Earth days. This means that lunar nights can be around two weeks long, with only the Earth and the stars in the sky. With all this to think about, scientists need to decide whether it would be better to follow a time zone on Earth, or for the Moon to have its own special zone, which would have much longer days.
Scientists must consider other problems too. For example, who should be responsible for keeping the time zone going? And how can it be made practical for astronauts to use?
There are more countries planning Moon trips in the future. The idea of creating a time zone on the Moon would make these easier. And if a lunar time zone is set up, scientists could create time zones for other planets like Mars.
