The Moon’s axis is only slightly tilted. Because of this, some craters near the poles never receive sunlight. These regions are called permanently shadowed craters. Temperatures can drop below -230°C. Ice can survive there for billions of years. These areas act like natural freezers.
Time matters because these regions preserve ancient material. They contain records of early solar history. Nothing disturbs them.
It also makes them valuable for exploration. Water ice could support future lunar bases. Darkness hides opportunity.
Some lunar craters haven’t seen sunlight for over 2 billion years.
[NASA, nasa.gov]