Everything he had seen over the last week fell into place. He stood, staggering a little under the impact of the idea, and circled the work-table as if imitating a moon. When there had been only two dots, the others could have been behind the big planet—or before it. And he saw also that the orbiting moon now outermost could perhaps have moved so far away from Jupiter as to be outside his eyepiece’s little circle. The shifts in position suggested they were moving fairly quickly. Earth’s moon took only twenty-eight and a half days for its orbit. These four seemed faster, and perhaps could be moving at differing speeds, just as the planets moved at differing speeds in the sky.
If he were right, then he could expect to see several more things. Seeing the orbits side-on, the moons would appear to slow down as they approached their maximum distance from Jupiter, and be fastest when right next to it. They would also disappear when behind it (or before it) in a regular pattern, and always reappear on the other side, never on the same side. Repeated observations should make it possible to sort out which moon was which, and determine which orbited closest to Jupiter and which farthest away. Knowing that would help him to calculate each orbital period, and that would allow him to keep steady track of them, and even predict where they would be, in a Jovian ephemerides of his own device.
“My God,” he said, overwhelmed at these thoughts, suddenly weeping, feeling he should fall to his knees to say a prayer in thanks to God—only his knees were too stiff; he was too cold. Anyway, it was looking through the glass that was the prayer. “I’m the first in the world!”
Which—when he recovered from the awe of it—really should be something he could turn to advantage. A truly new thing in the world—how could it not be useful? He had to hop about in the frigid night air to express his happiness. Mazzoleni and the rest would have laughed to see it, as they had laughed all the times they had seen it, after one good discovery or another. But none so good as this! He chortled; he shuffled around the terrace in a dance with the spyglass as his partner. He felt an urge to ring the workshop bell; he even began to walk toward the workshop, to wake Mazzoleni and the rest, to share the news with somebody. But he was the bell he wanted to ring, and if he woke the others, Mazzoleni would just nod and grin his gaptoothed grin, and be pleased that the new instrument was working better than the previous one. What went on in the sky did not matter to him.
So Galileo stopped in his tracks and returned to the terrace. He recommenced his little contradance around the tripod and worktable, singing nonsense words to himself under his breath. Tomorrow he would write up his news, and publish it as soon as possible after that, to share it with the world. Everyone would know, everyone would look and see. But only he would be first—first always, first forever. Feeling warm in his cloak, he settled on the stool under the tripod to look some more.
Then there came a knock at the garden gate. And he knew who it was.
Chapter three
Entangled
Galileo walked stiffly toward the gate, feeling his heart pound. The knock came again, a steady tap tap tap. He reached the gate and pulled up the crossbar, feeling a sweat of trepidation.
It was indeed the stranger, tall and gaunt in a black cloak. Behind him hunched a short, gnarled old man, carrying a leather satchel over one shoulder.
The stranger bowed. “You said you would enjoy to look through a spyglass of my own.”
“Yes, I remember—but that was months ago! Where have you been?”
“Now I am here.”
“I’ve seen some amazing things!” Galileo could not help saying.
“You still wish to look through what I have?”
“Yes, of course.”
He let the stranger and his servant in the gate, his unease written all over his face. “Come out to the terrace. I was there when you knocked, looking at Jupiter. Jupiter has four stars orbiting it, did you know that?”
“Four moons. Yes.”
Galileo looked disappointed, also disturbed; how had the stranger been able to see them?
The stranger said, “Perhaps you would enjoy to see them through my instrument.”
“Yes, of course. What is its power of magnification?”
“It varies.” He gestured at his servant. “Let me show you.”
The man’s ancient servant looked familiar. He wheezed unhappily under his load. On the terrace, Galileo reached out to help him lower the satchel, briefly holding him above the elbow and against the back. Under his coat the man felt like nothing but skin and bone. He slipped out from under the strap of the long bag carelessly, before Galileo had quite gotten hold of it, and it hit the pavers with a thump.
“It’s heavy!” Galileo said.
The two visitors pulled a massive tripod from the satchel, and arranged it next to Galileo’s instrument. Then they drew a big spyglass out of the case. Its tube was made of a dull gray metal, like pewter, and they held it by both ends to lift it. It was about twice the length of Galileo’s tube, and three times the diameter, and clicked onto the top of its tripod with a distinct snap.
“Where did you get that thing?” Galileo asked.
The stranger shrugged. He glanced at Galileo’s tube, then spun his on its tripod with a light flick of the wrist. It stopped moving when it came to much the same angle as Galileo’s, and with a small smile the stranger gestured at the instrument.
“Be my guest, please. Have a look.”
“You don’t want to sight it?”
“It is aimed at Jupiter. At the moon that you will call Number Two.”
Galileo stared at him, confused and a little afraid. Was the thing supposed to be self-sighting? The man’s claim made no sense.
“Take a look and see,” the stranger suggested.
There was no reply to that. It was what he had been saying himself, to Cremonini and everyone: Just look! Galileo moved his stool over to the new device, sat down, leaned forward. He looked into the eyepiece.
The thing’s field of vision was packed with stars, and seemed large—perhaps twenty or thirty times what Galileo saw through his glass. At its center, what he took to be one of the moons of Jupiter gleamed like a round white ball, marked by faint lines. It was bigger than Jupiter itself was in Galileo’s glass. The harder Galileo looked, the more obviously spheroid the white moon became, its striations more visible. It stood out like a snowball against the stars, which burned in their various intensities against a depth of velvet black.
It appeared that the white ball, clearer than ever to his sight, had faintly darker areas, somewhat like Earth’s moon; but more prominent by far was its broken network of intersecting lines, like the craquelure on an old painting, or the ice on the Venetian lagoon in cold winters after several tides had cracked it. Galileo’s fingers reached for a quill that was not there, wanting to draw what he saw. In some places the lines appeared in parallel clusters, in others they rayed out like fireworks, and these two patterns overlapped and shattered each other repeatedly.