“Sounds fair enough.” I didn’t ask why they hadn’t done their own exploring. Like most sentient vegetarians, puppeteers find discretion to be the only part of valor.

“Two humans named Peter Laskin and Sonya Laskin wished to use the ship. They intended to come within one mile of the surface in a hyperbolic orbit. At some point during their trip an unknown force apparently reached through the hull to do this to the landing shocks. The unknown force also seems to have killed the pilots.”

“But that’s impossible. Isn’t it?”

“You see the point. Come with me.” The puppeteer trotted toward the bow.

I saw the point, all right. Nothing, but nothing, can get through a General Products hull. No kind of electromagnetic energy except visible light. No kind of matter, from the smallest subatomic particle to the fastest meteor. That’s what the company’s advertisements claim, and the guarantee backs them up. I’ve never doubted it, and I’ve never heard of a General Products hull being damaged by a weapon or by anything else.

On the other hand, a General Products hull is as ugly as it is functional. The puppeteer-owned company could be badly hurt if it got around that something could get through a company hull. But I didn’t see where I came in.

We rode an escalladder into the nose.

The lifesystem was in two compartments. Here the Laskins had used heat-reflective paint. In the conical control cabin the hull had been divided into windows. The relaxation room behind it was a windowless reflective silver. From the back wall of the relaxation room an access tube ran aft, opening on various instruments and the hyperdrive motors.

There were two acceleration couches in the control cabin. Both had been torn loose from their mountings and wadded into the nose like so much tissue paper, crushing the instrument panel. The backs of the crumpled couches were splashed with rust brown. Flecks of the same color were all over everything: the walls, the windows, the viewscreens. It was as if something had hit the couches from behind: something like a dozen paint-filled toy balloons striking with tremendous force.

“That’s blood,” I said.

“That is correct. Human circulatory fluid.”

Twenty-four hours to fall.

I spent most of the first twelve hours in the relaxation room, trying to read. Nothing significant was happening except that a few times I saw the phenomenon Sony Laskin had mentioned in her last report. When a star went directly behind the invisible BVS-1, a halo formed. BVS-1 was heavy enough to bend light around it, displacing most stars to the sides, but when a star went directly behind the neutron star, its light was displaced to all sides at once. Result: a tiny circle which flashed once and was gone almost before the eye could catch it.

I’d known next to nothing about neutron stars the day the puppeteer picked me up. Now I was an expert. And I still had no idea what was waiting for me when I got down there.

All the matter you’re ever likely to meet will be normal matter, composed of a nucleus of protons and neutrons surrounded by electrons in quantum energy states. In the heart of any star there is a second kind of matter, for there the tremendous pressure is enough to smash the electron shells. The result is degenerate matter: nuclei forced together by pressure and gravity but held apart by the mutual repulsion of the more or less continuous electron “gas” around them. The right circumstances may create a third type of matter.

Given: a burned-out white dwarf with a mass greater than 1.44 times the mass of the sun—Chandrasekhar’s Limit, named for an Indian-American astronomer of the 1900s. In such a mass the electron pressure alone would not be able to hold the electrons back from the nuclei. Electrons would be forced against protons—to make neutrons. In one blazing explosion most of the star would change from a compressed mass of degenerate matter to a closely packed lump of neutrons: neutronium, theoretically the densest matter possible in this universe. Most of the remaining normal and degenerate matter would be blown away by the liberated heat.

For two weeks the star would give off X-rays as its core temperature dropped from five billion degrees Kelvin to five hundred million. After that it would be a light-emitting body perhaps ten to twelve miles across: the next best thing to invisible. It was not strange that BVS-1 was the first neutron star ever found.

Neither is it strange that the Institute of Knowledge on Jinx would have spent a good deal of time and trouble looking. Until BVS-1 was found, neutronium and neutron stars were only theories. The examination of an actual neutron star could be of tremendous importance. Neutron stars might give us the key to true gravity control.

Mass of BVS-1: 1.3 times the mass of Sol, approx.

Diameter of BVS-1 (estimated): eleven miles of neutronium, covered by half a mile of degenerate matter, covered by maybe twelve feet of ordinary matter.

Nothing else was known of the tiny hidden star until the Laskins went in to look. Now the Institute knew one thing more: the star’s spin.

“A mass that large can distort space by its rotation,” said the puppeteer. “The Laskins’ projected hyperbola was twisted across itself in such a way that we can deduce the star’s period of rotation to be two minutes twenty-seven seconds.”

The bar was somewhere in the General Products building. I don’t know just where, and with the transfer booths it doesn’t matter. I kept staring at the puppeteer bartender. Naturally only a puppeteer would be served by a puppeteer bartender, since any biped life-form would resent knowing that his drink had been made with somebody’s mouth. I had already decided to get dinner somewhere else.

“I see your problem,” I said. “Your sales will suffer if it gets out that something can reach through one of your hulls and smash a crew to bloody smears. But where do I come in?”

“We want to repeat the experiment of Sonya Laskin and Peter Laskin. We must find—”

“With me?”

“Yes. We must find out what it is that our hulls cannot stop. Naturally you may—”

“But I won’t.”

“We are prepared to offer one million stars.”

I was tempted, but only for a moment. “Forget it.”

“Naturally you will be allowed to build your own ship, starting with a No. 2 General Products hull.”

“Thanks, but I’d like to go on living.”

“You would dislike being confined. I find that We Made It has reestablished the debtor’s prison. If General Products made public your accounts—”

“Now, just a—”

“You owe money on the close order of five hundred thousand stars. We will pay your creditors before you leave. If you return—” I had to admire the creature’s honesty in not saying “When.” “—we will pay you the residue. You may be asked to speak to news commentators concerning the voyage, in which case there will be more stars.”

“You say I can build my own ship?”

“Naturally. This is not a voyage of exploration. We want you to return safely.”

“It’s a deal.” I said.

After all, the puppeteer had tried to blackmail me. What happened next would be its own fault.

They built my ship in two weeks flat. They started with a No. 2 General Products hull, just like the one around the Institute of Knowledge ship, and the lifesystem was practically a duplicate of the Laskins’, but there the resemblance ended. There were no instruments to observe neutron stars. Instead, there was a fusion motor big enough for a Jinx warliner. In my ship, which I now called Skydiver, the drive would produce thirty gees at the safety limit. There was a laser cannon big enough to punch a hole through We Made It’s moon. The puppeteer wanted me to feel safe, and now I did, for I could fight and I could run. Especially I could run.