At the peak of the Apollo programme, when the US wanted to get a man on the moon above all else, Nasa accounted for 4.5% of the federal government budget. Today it is a fraction of that - about 0.6% or thereabouts.
It's a striking comparison.
And look at the results. Between 1969 and 1972, the US got men on the moon six times.
Then it all stopped. They cancelled the remaining three planned trips (Apollo 18, 19 and 20). Since then most people probably barely realise how far away from the moon man has remained.
The International Space Station (ISS) and the space shuttles which visit it hang out in low earth orbit. If the journey to the moon is equivalent to the distance from London to New York, going to the ISS is like a voyage from Westminster to Chelsea. It is a thousandth of the number of kilometres.
It does fortunately mean you don't need a telescope to see the ISS; household binoculars will do. It's quite fun. You can even track its whereabouts to find out when to look up into the sky.
But the sad implication is that the manned distant space travel - like supersonic aeroplane travel - has moved backwards rather than forwards.
What interests me is the very human factor that has driven all of this.
Is it funny that America invested so much in getting men to the moon in the 1960s when it was involved in the expensive Cold War with the Soviets and invests so much less now (relative to GDP) when it has a clearer position as the monopoly superpower?
No it's not funny - it was obviously the Cold War that did it.
The depressing conclusion is that as a species, we tend to concentrate our minds on big things not so much for the advances in pure science they bring, but for the lift they give us relative to our competitors.
When the lift is not needed, or when the competitors are not there, the motivation seems to diminish.
Or to put it another way, Nasa's problem these days is that there is no race for prestige to be won. The arguments for expensive space travel have to be made on scientific grounds - far more shaky in budget arguments than national pride.
Of course, Nasa does have grand plans to go back to the moon and beyond. The Constellation Programme aims to get people beyond low earth orbit again. For evidence of its progress you can see the photo of me walking on Mars itself inside the campus at the Johnson Space Centre in Houston.
It's a small mock Mars landscape, in fact. And 20 metres away is a moon landscape. They're both designed for training astronauts in costume.
But the Constellation Programme is under review. There is an economic crisis on. The target date of 2020 to get Americans off the ground and back on the real moon may well not be met.
Nasa would probably be in a lot better shape if the enemies of the West were more interested in running a flight to Mars than running around in the caves of Waziristan.