The silence was astounding. As the airlock opened, a sudden roar faded to nothing. He released the gunnels, and the gust of evacuated air lifted him from his feet, carrying him out. Gil had been in space many times before, but never like this. Space was dark and empty. Yet beyond the airlock, he emerged into a blizzard.

There was a spray of snow: tiny fragments of ice floating off into space. His airlock kicked up a gale, sending it flying in every direction. As the debris settled, he took in his surroundings. He was on a precipice; above, a blocky mountain stretched to ambitious heights, capped with snow. Beyond its peak, the ice and snow flitted off into space, lost among the endless stars.

Lost in the endless night, he felt as though he were stationary. But he was moving: the comet was careening through space at over 30,000 kilometers per hour. Ahead, the sun was growing larger as the ancient rock approached perihelion. No human had ever set foot on a comet before. But he couldn’t stay long. Even now, the ground beneath him was beginning to crack. As the comet neared the sun, those cracks would widen into fissures. The comet would fracture. He couldn’t be there when that happened.

Though the comet was vast, its gravity was weak. Even with his weighted suit, he walked carefully, lest an errant step send him freewheeling into space. Hoisting his pack, he wiped the snow from his visor, and began his lonely trek. The peak ahead of him was the result of an ancient cycle of death and rebirth: the comet accreted as it barreled through the dusky wastes of the Oort Cloud, before melting and fracturing as it swung around the sun. While most of the comet was composed of ice, the mountain was not. Thus it had withstood the test of ages, towering over the comet’s frozen surface.

By Earth standards, it wasn’t overly tall: less than a kilometer to its jagged summit. And without Earth’s gravity to contend with, it would be an easy climb. So he began his long trudge through a cosmic blizzard, bound for the tallest peak. He arrived at its base, and looked up. High above, the mountain poked out above the squall. His eyes on his goal, he withdrew picks from his pack, and dug in. The ice was solid, which helped. He planted his first pick, then hoisted himself up, digging the spiked toes of his boots into the ice. Then he planted his second, again shuffling upwards.

It was punishing. Visibility was low. The snow caked to his visor, blocking his vision. Periodically he was forced to release one of his picks to wipe it away, before resuming his climb. He’d never climbed a mountain before, but he’d trained for this mission for years. Still, his training couldn’t prepare him for everything, and the lack of vision was a surprise. But he kept going. He’d worked too hard to give up now.

At twenty meters, the blizzard began to fade. But the going was tougher; the ice was thinner, more tenuous. His boots slipped as he fought to drive his picks into the surface. His pace slowed. He began to tire. Despite the extreme cold he was sweating in his suit. He would have given anything to wipe the sweat from his brow. He’d have given everything and more to itch his nose.

At thirty meters, the blizzard gave way at last. He’d climbed above the snow line, and now he found himself looking down at the snow. He found a crag in the rock. It was narrow, no more than half a meter across, but he’d been climbing for some time. He was fatigued; he needed rest. So he tethered himself to the rock face with a piton, and sat as best he could. He was breathing heavily. Closing his eyes, he focused on his breathing, slowing his heart rate. His breath was the only sound to be heard. The silence was absolute.

He looked out, peering into the void. Ahead, the sun loomed large. Though he knew it wasn’t possible, he could have sworn it was noticeably larger than when he had arrived. Regardless, it was getting closer, and here the sun was his enemy. Its heat had already begun to melt the ice; the blizzard was proof of that. Every minute he stayed, he ran the risk that a large fragment would break away, carrying him with it as it drifted into space. Time was precious here. He’d rested long enough. So he tilted his head to take a sip of his suit’s water, detached his piton, and resumed climbing.

At this height, the going was rough. The ice had all but vanished, replaced by hard, barren rock. He had no hope of digging into it with his picks. Instead, he resorted to working them into narrow nooks and crannies in the rock face. The spikes on his boots helped him keep his footing as he clung to the rock. He climbed as fast as he could, eager to reach the top before he was exhausted. Now and then, one of his picks would slip. He’d gasp, holding fast to the other pick as he dangled. He’d close his eyes, count to ten, and then find a new spot for his picks. And so it went. He had no idea how long he’d been climbing. He fought the urge to check his chronometer. Doing so would lead to anxiety. He needed to focus.

He climbed forever, immersed in perpetual night, until at last he could see the top. The peak began to narrow, and he climbed faster and faster, throwing caution to the wind. He was so close. He could see it. When at last he reached the summit, he found it was narrow: the slanted peak was no more than two meters across. With effort, he hoisted himself onto it, and stood at last. He quickly unfastened his pack, kneeling to unpack the sensors. Yet he paused, turning to look out into space. He stood, slowly, and turned, taking in the view. All around him, space stretched endlessly: stars and planets and galaxies that went on forever. He’d been in space many times before. He’d seen the stars every day for years. It had been a long journey, a difficult climb. But now, gazing upon a view no other human had ever seen, he knew it had all been worth it.