How can there be ice on the moon?

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I actually have an issue in regards to the ice on the moon. How is that possible? – Olaf, 9 years old, Hillsborough, North Carolina


We are fortunate to survive a water world. More than 70% of the Earth’s surface is roofed with water.

The Earth is about 94 million miles from the Sun. That is inside the Goldilocks zone: the place in our solar system where a planet has just the best temperature for water to exist as a liquid in oceans and rivers and as ice on the North and South Poles.

The Earth also has an environment greater than 9,650 kilometers thick, stuffed with oxygen that we will breathe. This atmosphere, along with a giant magnet at the middle of the earthprotects us from the sun harmful radiation, especially solar wind and cosmic radiation.

But the moon hardly looks like a water worldor perhaps a place with a couple of puddles. It has a worn internal magnet and a Atmosphere so weak it’s practically a vacuum. There aren’t any clouds, no rain, and no snow, only a sky made up of nothing however the blackness of space, with a surface baked by the sun. The moon's temperature reaches 134 degrees Celsius through the day and drops to -153 degrees Celsius at night.

But as a scientist who explore space And working on the event of technologies who’re searching for water, we will definitely say: Yes, there may be water on the moon.

One day, astronauts may have the option to make lunar water drinkable.

The discovery

For an extended time, astronomers and other scientists thought moon water was unlikely. Finally Apollo astronauts brought many rock samples from the moon and all of them were dry, no water was detectable.

But recent visits by spacecraft have shown that water is present there. In 2009, NASA crashed a spacecraft – the Lunar Crater Observation and Sensor Satellite, or LCROSS – into the lunar surface, into the Cabeus crater. When that happened, Water ice was ejected.

This confirmed to scientists that there was water ice at the underside of the craters. But determining the quantity of water can be difficult. The 10,000 or so lunar craters are essentially large holes, with areas so shaded that the sun never shines in. These places are really cold, well below -300 F (-184 C). Once these frozen water molecules get stuck within the craters, they stunning much stay ceaselessly unless they’re dislodged by heat or energy. They are unlikely to melt naturally. evaporate or sublimate as steam – it's just too cold in there.

But that doesn’t mean that water is barely stored in craters. In 2023, scientists SOFIA, the Stratospheric Observatory for Infrared Astronomylooked for water on the lunar surface in areas that weren’t as cold because the craters. And they found it – not on the bottom, but probably contained in the soil grains.

Nobody yet knows how much water there may be on the moon and the way deep it extends. But one thing is for certain: there may be way more water on the moon than scientists initially thought.

Artist's depiction of a moon base with round huts in the foreground and the Earth in the background.
Water can be crucial for astronauts living in lunar colonies.
Marcos Silva/iStock via Getty Images Plus

Comets and volcanoes

How did water get to the moon? Nobody knows needless to say, but there are some theories.

Eons ago, comets – essentially frozen, dirty snowballs – crashed into the Earth, forsaking their cometary water. This is certainly one of the ways in which the Earth developed its oceans; perhaps the moon also obtained a few of its water in this fashion.

Other scientists consider Old volcanoes on the moon released water vapor once they erupted billions of years ago. Eventually, this vapor settled to the surface as frost. Over time, layers of this frost accrued, particularly on the poles; much of it could have found its way into the lunar craters as ice.

Drinking water for astronauts

Water is heavy. Transporting it to the moon in a spaceship could be expensive. Therefore, it makes more sense for astronauts to seek out a way use the water that already exists on the moon.

But lunar water just isn’t drinkable in itself; it comprises small particles of lunar soil and possibly other molecules. Astronauts living in lunar colonies must purify the collected water. This is a difficult process that considerable effort and resources.

There is a plan to drill and seek for water, just as people within the Middle Ages looked for gold underground. Gold rush within the nineteenth centuryThe comparison just isn’t bad – water on the moon could sooner or later be more useful than gold on Earth.

And not only for drinking. Water is of course made up of two parts hydrogen and one part oxygen; it might be split. This is a win-win situation: astronauts can use the hydrogen as rocket fuel and the oxygen as breathable air. With the sun as an energy source, the Water splitting might be feasible.

Return to the moon and Establishing a everlasting base is a big commitment requires many years of labor, billions of dollars, the cooperation of many countries, and lots of latest technologies But because the world enters this dramatic latest chapter of space exploration, the pioneers are at risk of Destruction or pollution of a singular environment that has existed for billions of years – and lots of scientists feel a deep commitment in order to not repeat the painful lesson we are actually learning here on earth.


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