How Cold Is The Moon?

The moon, Earth’s natural satellite, has long fascinated observers from Earth. It is a near-constant presence in the night sky, glowing brightly against the blackness of space.

From ancient cultures with primitive understanding of science, to our modern societies with our knowledge, the moon has consistently fascinated us. 

It is only recently that mankind has been able to leave our own atmosphere and reach the moon, but man has wanted to visit the moon since our ancestors first looked up to the night sky. The moon remains a source of beauty and wonder that has not diminished.

Perhaps one day mankind will live on the moon, but today - no, we cannot yet make the moon support life.

The temperatures that the moon reaches are so extreme that astronauts must take extremely expensive measures to be able to survive even a moment there - and that’s not to mention the total lack of breathable air!

In fact, the moon barely has an atmosphere at all - one of the reasons that it is so inhospitable to us.

What Temperatures Does The Moon Reach?

The moon reaches temperatures that would be considered extreme by the standards of Earth. Indeed, an astronaut without special protection couldn’t survive for very long on the moon at all!

At its hottest, the lunar equator reaches up to 260°F (127°C), due to the sun beating down on the moon’s surface for the entirety of the moon's extremely long days. If we were to experience that temperature on earth, we’d be literally cooked!

The moon gets cold too - very cold. At the other extreme, a night on the moon is equally as long as a day, and sees the moon reach lows of -280°F (-173°C) at its equator. That’s so cold that, again, there’s just no way we could survive it unprotected.

Indeed, the temperatures reached on the moon are far in excess of those reached on Earth - and stay at either extreme for nearly half a month each time!

Of course, these are the extremes of temperature. The moon actually isn’t equally hot or cold all at the same time. Due to lunar rotation, both the near side and far side of the moon are heated by sunlight (or cooled by its lack).

However, these extreme temperatures are reminders of just how difficult surviving on the moon would be!

How Long Are Days And Nights On The Moon?

Days and nights are extremely long on the moon. Most of us are used to 24 hour day/night cycles here on Earth - although there are of course some places that have wildly different periods of light and dark than others. However, the day and night cycle on the moon is so different to ours!

The moon orbits the Earth once every 27 days. It also takes 27 days for the moon to rotate once on its axis - meaning that the same side of the moon is facing us. This could lead us to mistakenly believe that a day on the moon lasts as long as a day here - but a day on the moon is much longer!

Days on the moon actually last for 13.5 days, due to the speed of the moon’s rotation. This means that the high temperatures of the moon last for nearly 2 earth weeks! And likewise, the extreme lows on the moon also last for as long.

So, surviving on the moon would be a matter of dealing with these 2 extremes in temperatures, and anything in between - and would mean living with a day/night cycle that takes most of an Earth month!

Why Does The Moon Get So Hot?

There are two chief reasons why the moon reaches such extreme temperatures.

One is of course, because of the length of the days and nights on the moon. A day on the moon lasts so long that parts of the surface can be exposed to the heat and light of the sun for days on end - nearly 2 weeks for parts of the surface catching the most sunlight!

Likewise, a night on the moon means no sunlight for nearly 2 weeks - which means 2 weeks without being exposed to a heat source. No wonder it gets so hot and cold up there!

Also, the moon barely has an atmosphere! Although it’s common to think of the moon as having no atmosphere at all, it does in fact have an extremely thin atmosphere.

However, unlike the earth’s atmosphere - layers of gases which, amongst other things, shield us against much of the heat from the sun, and slow down the loss of heat on the side of the planet not exposed to sunlight - the moon’s atmosphere is extremely thin, and does very little to prevent either loss or gain of heat.

Without this shielding effect that the atmosphere provides, the surface of the moon bears all of the brunt of the sun’s heat! And, likewise, when that same part of the surface is in darkness, the thin atmosphere does little to nothing to prevent that heat from escaping the moon!

How Did Astronauts Survive The Temperature On The Moon?

Walking safely on the moon took a massive amount of planning and preparation! Due to the extremes in temperature on the surface of the moon, much care had to be taken to ensure that the astronauts were able to walk safely on the surface.

Firstly, choosing the right time to land was crucial! The missions were planned to take place at lunar dawn, which would let the astronauts walk on the surface before it had been able to fully heat up to an extreme temperature.

As the atmosphere of the moon is so thin that it’s reasonable to treat the moon as if it doesn’t have one, there aren’t any gases to speak of on the moon. This means that heat can’t be lost through convection or conduction to the air like on earth - there isn’t any air!

The best way for the astronauts to deal with the heat of the sun, therefore, was to not receive most of it in the first place!

Not only did this mean avoiding the time with the hottest temperatures, but it also meant designing their suits to reflect as much of the heat of the sun as possible. Their suits were designed to reflect almost 90% of the light that hit them!

Conclusion

The moon reaches some very extreme temperatures, far higher and lower than on Earth! Hopefully this article has helped teach you something about temperatures on the moon!