“Stay down!” Bram shouted.
His voice cut through the sudden babble, and people who had started to move clung to their mats. Bram thumbed the intercom switch and repeated his warning for those in their quarters.
Tidal forces changed their orientation as Yggdrasil, now in orbit around the outside hole, swung loose on its tether. The probe, uselessly spitting hadronic photons, must similarly have been trying to align its axis with its strange new parent body.
Bram fervently and irrationally hoped the probe’s drive was pointed down, not up. Not that it would significantly matter in these few minutes and in view of the greater forces acting on the vehicle. In any case, he reminded himself, breaking free of orbit now would be every bit as deadly as diving into the black hole itself.
Equipment went sliding and crashing. People gasped as they felt the tidal pseudogravity change its direction. The hole didn’t care which axis it struck through the wider diameter of the dumbbell-shaped body it had captured, but Yggdrasil, bless it, did, and the tree’s struggle to “remember” its Bobbing Day vertical saved the humans from injury.
“Hold on to something if you can!” Bram shouted. “Try to stay in contact with the floor!”
Yggdrasil held together. Jun Davd had done his calculations well. The smaller black hole, with a solar-system-size circumference of over a billion and a half miles, was big enough, and their orbital distance from it great enough that tidal forces could not pull the tree apart. And the size of an individual human being was too insignificant to matter. Bram could feel the differential in the tug between his head and his feet, but it was no worse than the second-rate artificial gravity to be found in a spinning space vehicle that happened to have a diameter of only forty or fifty feet.
“Here comes the fun part,” Jao said over the loudspeaker.
Yggdrasil swooped around the focus of its orbit. It was now attaining the inside loop of its curve. It was no longer speeding around the black hole in a direction contrary to the hole’s own path around the parent hole, but was picking up fifty thousand g’s worth of acceleration from the hole’s orbital motion.
All for free, as Jao had pointed out. It was fifty thousand gravities that would have crushed them to paste if they had not been in free fall around the body that was providing it.
The only scary part of it was the fact that the inside loop was taking the treeful of humans between the two black holes.
“Oh, Bram,” Mim whispered, squeezing his hand in a death grip. “Can such things be?”
The screen was blinding, even though it showed a bowdlerized version of the radiance outside. They passed between cascades of fire that sheeted to infinity. The eye followed those ravening walls along a path of bent light that made nonsense of perspective—on and on past the point where they should have recurved and eclipsed themselves.
At the center of each infinity, the fires poured into an iris: nothingness surrounded by violet inferno.
“I wasn’t sure we’d be able to see the holes themselves,” Jun Davd’s awed voice said. “I thought the accretion disks and the surrounding infall would block them from sight. But geometry doesn’t mean anything here. We’re within a few billion miles of each of them—less than a light-day away. If you’re willing to accept an arbitrary definition of distance in the vicinity of gravitational fields like these, that is.”
Bram’s fear that there would be no path between the two accretion disks proved to be unfounded. What had appeared from a distance to be a merging of the twin vortices was a less substantial barrier up close. The accretion disks traded material, it was true, but the gaseous zone between them was tenuous enough to pass through. And Yggdrasil wasn’t going to be here long enough to worry about orbital decay. As they plunged between the fountaining sheets of flame, a curtain seemed to open up continually before them.
There was a moment when a giant eye looked in at them through the observation wall. People cried aloud in wonder. In the yawning eternity that the hole’s gravity had made of time, light was downshifted even more than Yggdrasil’s tremendous speeds had done thus far. Theoretically, there should have been nothing visible.
And nothing was what they were seeing.
Then the hole flung them away. The tree whipped around the loop, its path bent back on itself, and headed out of the galaxy. The transfer of orbital energy had been tremendous, and the hole’s precession had given the tree the additional vector that would angle its path above the ecliptic.
The weight of acceleration returned. People picked themselves up and started to move about. The g-forces were back to normal now. There was no need to force the pace. Whatever the danger from the front of radiation that would inevitably overtake them at some undetermined time in the years ahead, they had successfully navigated between those terrible whirlpools without being caught in the ultimate collapse.
Bram helped Mim to her feet. Together they went to the view wall. Other people were lined up along the safety rail, looking out.
There was something to see now, for the first time since the starbow had moved out of sight.
The universe was filled with light. Light of all colors, in wisps and ribbons and streamers.
An elongated blob of mottled blues and greens stretched, writhed, broke up into smaller blobs of violet and orange. A long pennant of pale blue flapped and disintegrated into a thousand filaments. Iridescent tendrils reached after the craft and fell behind. The striations of color played against a background of white radiance that cast long multiple shadows behind the people at the rail.
Yggdrasil was riding the shock waves out of the galactic center. In the nearby volume of space, collimated beams of accelerated matter were traveling in the same relativistic frame as Yggdrasil and shedding some of their radiation in the visible part of the spectrum.
The grateful tree dwellers drank in the spectacle, chattering happily after the tension of the past hours. Nobody was stopping to think about what it meant.
“It’s beautiful,” Mim said.
Bram said nothing. It was the beauty of death.
“It’s hard to believe two hundred thousand years have gone by since we left the galaxy,” Marg said. The tiny curved smile on her lips indicated an attempt at whimsy. “You don’t look a day older, Mim. In fact, quite the reverse.”
Mim, holding the new baby, beamed. “I’m going to name her Lydis,” she said. “It comes from the tonality that Beethoven chose for a quartet movement he intended as a song of thanksgiving.”
“Very appropriate,” Orris said, “seeing that she was born on Safepassage Day.”
“I was going to wait a few more years before getting pregnant,” Mim said. “But then I decided I was young enough.”
“You’re not going to get much younger,” Marg said. “None of us are.”
Marg’s own baby was two years old now. She and Orris had finally taken the plunge when Jun Davd had announced that they had officially left the exploding galaxy behind. There had been a rash of births that year.
“Oh, I don’t know.” Jun Davd laughed, trying to extricate a gnarled finger from the baby’s grip. “Some of us elders still have quite a few years to go before we lose our wrinkles.”
Bram, hovering proudly over Mim and the baby and trying not to look too smug, said, “I don’t like to think of it as two hundred thousand years. Let the outside universe take care of itself. I prefer to count it in Safepassage Days—three more of them. We’re all still alive, and we’re even ahead of schedule.”
The first Safepassage Day had been celebrated the year after the black hole maneuver. Nobody had thought it up—it had just seemed to happen by itself. It came the day after Bobbing Day, and the two holidays had naturally merged into one extended festivity. A new set of rituals had quickly sprung up around Safepassage Day, with gift giving, overeating, and much hilarity. Bobbing Day was still observed, though the reason for it was now gone, with Yggdrasil under spin. It was mostly for the children, who celebrated with miniature trees, candy, and little gaily painted plumb bobs.