Having dropped tantalising hints days ago about an "exciting new discovery about the Moon", Nasa has revealed conclusive evidence of water on our only natural satellite.
This "unambiguous detection of molecular water" will boost Nasa's hopes of establishing a lunar base.
The aim is to sustain that base by tapping into the Moon's natural resources.
The findings have been published as two papers in the journal Nature Astronomy.
While there have previously been signs of water on the lunar surface, these new discoveries suggest it is more abundant than previously thought. "It gives us more options for potential water sources on the Moon," said Hannah Sargeant, a planetary scientist from the Open University in Milton Keynes, told BBC News.
Where to put a Moon base is largely focused on where the water is."
The US space agency has said it will send the first woman and next man to the lunar surface in 2024 to prepare for the "next giant leap" - human exploration of Mars as early as the 2030s.
However, space scientist Dr Duncan Steel, who has worked for both NASA and the European Space Agency, said the discovery doesn't mean there is life on the moon.
"For sometime we've suspected there is water on the moon in the form of ice, there will never be liquid water on the Moon, it would either be frozen or in a vapor form.
"In the vacuum of space water would go from the solid, so ice into vapor if it was heated at all, it wouldn't look like liquid water as we know here on Earth," he said.
The water is like a frost in craters near the Moon's poles which are always shaded from sunlight, he said.
"This is a big deal because if we know there is water on the Moon we can use it when we set up a scientific outpost on the moon, it can be used for astronauts to drink, to shower and we can even split it to get the oxygen out for people to use it to breathe.
"We can even get the hydrogen out which can be used as rocket fuel - it sounds like science fiction but we are getting close to being able to have scientists stationed on the Moon," Steel said.
There are estimates that there could be as much as a litre of water per cubic metre of soil on the Moon's surface.
"That's a substantial amount and is a lot more than what's been suspected to be there in the past, so this is a very interesting discovery."
"It will be a great day when we can get on the Moon and dig deeper into the surface to see what is below, certainly the target of future missions is to go closer to the poles in order to look at this craters in greater detail," he said.
Professor of Physics at Auckland University Richard Easther said scientists could make the discovery by looking at infra red light which is reflected off the Moon's surface.
Prof Easther said with so much water vapor in the Earth's atmosphere, the only way to read the Moon's surface is to do tests in space or from an aircraft which is flying at a sufficient altitude so that it doesn't pick up what's in the Earth's atmosphere.
"This discovery tells us a lot about he mineralogy of the Moon, but it also brings up a lot of questions which need to be answered like how it got there, how long its been there and so on."
Easther said the discovery and announcement has had many in the science world rolling their eyes, because it's not the first time water has been discovered on the Moon.
"It is big news, it's not necessarily a big breakthrough like what it's been touted as, there's been a lot of talk on social media about NASA's announcement.
"It's been a little hyped up, how many times can we claim that we've found water on the Moon this is at least the second if not third time its been discovered."
- BBC / RNZ