Now Spookie and Dyspepsia had never built a spaceship before. They’d never even seen one. Which turned out to be a good thing, because it gave them a fresh start, with new ideas.

Now NASA does it in a very expensive and uncomfortable way. That’s because they don’t work things out properly. Instead of having one person do the whole job, they have lots of people doing bits of it and not talking to each other. And then they do a cost-cutting exercise at the end, which makes everything a lot more uncomfortable for the spacemen than it might have been.

The way to do it, as Spookie told Dyspepsia, was to think of the simplest, cheapest way to do it to start with, then you’d have a bit of money left over, which you could spend on making it a lot more comfortable for the spacemen than it might have been.

If you’re making a spaceship for yourself to fly in, you’re jolly careful to make it comfortable. A lot more than you would if you were making it for other people. Dyspepsia certainly agreed with that. But she wanted to know how they could possibly make it both cheaper and more comfortable than a NASA space rocket?

So Spookie had to give her an example.

Living on Earth, as we do, is like living in a big invisible valley, due to Earth’s gravity. So to get to another planet you have to burn a lot of petrol just to get to the top of the hill, out of the invisible valley. After that, it’s all pretty flat and you can go where you like for nothing.

Now the heavier your car and passengers, the more petrol it takes to get to the top of the hill. Twice as heavy, twice the petrol, and so on. For every kilogram you want to lift up into space, you need 100 kg of rocket plus fuel.

So NASA thinks it’s best to burn all the fuel up right at the start so you don’t have to carry it up to the top of the hill, since the fuel itself needs more fuel to carry it up, and that fuel needs more fuel, and so on and so on. This means rockets have to whoosh off so fast it’s enough to tear your eyebrows off.

That’s one reason you never see an astronaut with eyebrows.

According to Spookie the NASA way of doing it was all wrong. Now Spookie was allowed to say that because she was a very clever cat. That’s because she used to belong to a very clever professor. Clever professors have no use for silly cats. In fact they rely on their cats to tell them when it’s time to have lunch and go to bed and things like that. So the cats have to be cleverer than the professors.

Dyspepsia asked Spookie to explain how it ought to be done. Spookie did so like this. She got a casserole out of the cupboard to stand for the spaceship. Into the casserole she put a Princess Leia dolly for Dyspepsia and a Yoda dolly for her, plus a Kit Kat bar for the food. Then she lifted the casserole slowly up in the air.

“That’s as fast as you really want to go,” she said, “if you want to keep your eyebrows on.”

Now Spookie hasn’t got very long arms. They’re only long enough to keep her nose from bumping on the ground when she stands on all fours. But Dyspepsia quickly got the point. With very very long arms, there’d be nothing to stop Spookie from steadily lifting the casserole all the way up into space. All the way to Mars, if she felt like it.

Spookie said “NASA thinks you’ve got to carry the fuel inside the spaceship, for the energy it needs to lift up, and to speed up.” She put a disposable lighter in the casserole to represent fuel. “But you don’t.” So she took it out again. Once more she lifted the casserole up in the air. “Where’s the energy coming from?”

“It’s in your arms,” said Dyspepsia. “It’s you, doing the pushing.”

“That’s right,” said Spookie. “Now why can’t NASA see that for themselves? It’s because Dr Wernher von Braun started them off in rockets, and they’ve never seen the need to change.”

Dyspepsia held her finger up straight and blinked her eyes, as if a pretend light bulb was going off in her head.

“So all we need is a cat with very very long arms, and we could be lifted all the way to Mars?”

“There’s no need to be sarky,” said Spookie. “Instead of a cat with very very long arms, we can use a microwave beam and keep it pointing at Mars. Then we simply ride along the beam, picking up all the energy we need on the way. It’s not rocket science.”

Dyspepsia looked doubtful. “If it’s that simple, perhaps somebody ought to tell NASA…”

“Who do you want to get to Mars first?” said Spookie. “NASA… or us?”

…to be continued.