Q&A: Going back to the Moon

Dr Paul Spudis is a scientist who has spent a large part of his career studying the Moon.

Spudis: The Moon can tell us about the early Earth

Now, he sits on the US presidential commission that will direct a new space exploration programme - to go back to the lunar surface, on to Mars and beyond. He told us how he thought the future would develop.

How do you view the commission's role?

We are there to advise the President. He made a speech at Nasa headquarters in January, outlining a new vision where America will return to the Moon and go to Mars and beyond.

The job of the commission is to examine ways to implement that vision - how to accomplish it; and to make suggestions and recommendations to the President on Nasa's plans.

If you can extract resources from the Moon and other objects and places in the Solar System, you've got the ability to create infrastructure in space

How excited are you about the thought of sending astronauts back to the Moon?

I think that fundamentally it has a chance to change the spaceflight paradigm.

Right now, we are limited to what we can lift off the Earth and if we can use the resources of space to change that equation, change the rules of the game, then we are only limited in what we can do in space by our imagination and not by what we can lift out of the Earth's gravity well. I am tremendously excited.

But why go back to the Moon? What is the point?

Fundamentally, the reason you want to go back to the Moon is to use it to create a space infrastructure.

New technologies will be required to go back to the Moon

Right now, we cannot go beyond low-Earth orbit. You go to the Moon to learn if humanity can live off-planet - that is the fundamental mission.

One of the things for me that was very encouraging in the President's speech was that he specifically mentioned new technologies designed to extract usable resources out of the Moon. To me, that's the key.

If you can extract resources from the Moon and other objects and places in the Solar System, you've got the ability to create infrastructure in space.

But the Moon is a bit dull isn't it?

Every place in the Solar System is unique and it has a story to tell. What we found in the last 40 years of exploration is that some parts of the Solar System retain the record of the earliest events - i.e. meteorites and asteroids, which formed immediately after the Solar System was created.

Then there was a period of very great violence and geological activity when the planets assembled and they melted and differentiated and they were bombarded by impactors and projectiles.

That's a record that is largely missing from the Earth [because of] erosion and plate tectonics. On the Moon, we can read and recover that record and understand the early bombardment history of the Earth including the time when life arose.

What kinds of resources are available on the Moon?

In terms of materials, beside the bulk lunar material which can make building blocks, we have found in the last 10 years that there are deposits of water-ice in the permanently dark areas of the poles of the Moon.

This will make the extraction of water from the Moon much easier. Water is useful for two reasons: one to support human life, both by drinking it and by breaking it down into hydrogen and oxygen (that you can breathe); and the other is, when you have hydrogen and oxygen, you can liquefy it and make rocket propellant.

No one underestimates the effort that will be required

Can you see a time when we have a permanently manned Moon base?

Ultimately, I think we will want to be on the Moon for a lot of different reasons, not just scientific ones, but for operational reasons, for cultural reasons. So there is no doubt in my mind, people will live permanently on the Moon. It may not happen in my lifetime, but it will happen eventually.

Can America afford the new hardware that will be needed?

A lot of the infrastructure that was needed before to take us to the Moon had to be created from scratch. We are much further ahead of the curve this time. We have a lot of the technologies that we didn't have before.

So, returning to the Moon is going to be cheaper in real terms than it was to go to the Moon 40 years ago. Secondly, the budget for the President's proposals is very cleverly constructed. Fundamentally, it assumes that Nasa will get the same amount of money for the next 10-20 years that it is getting now.

Currently, Nasa gets about $15bn a year. It rises very slowly with inflation. Over the course of the next 20 years that is upward of $150/160bn. That should buy you a significant amount of capability.