‘Hey,’ I said.

Elena didn’t reply. The lamps on her helmet illuminated her glittering face in the dark, like the icon of a saint. Her expression was impossible to read. She wasn’t crying. She wasn’t angry. She was just . . . looking.

‘That’s what’s different,’ she said at last. There was relief behind her words, the satisfaction of an itching problem solved.

‘What is?’ I asked.

She nodded at the daggers of ice, her headlamps changing their smooth surface from black to white. ‘It’s so clean.’ I didn’t understand, and my face must have said so, because she added: ‘Ever seen an iceberg flip?’

‘No,’ I said.

‘How about a glacier?’

‘A glacier . . . flip?’

Her eyes gave me one brief, chiding flick. ‘No, just a glacier, in general.’

The image was conjured, and her point was made. I pictured those oh-so-rare mountains of ice back home, with their dramatic streaks of grey and black that sometimes crowded out the whiteness entirely. The sort of large-scale ice humans are most likely to see on Earth is the ice that forms on land, and by nature, that ice is grubby. Even icebergs, which you might think are washed clean by the waves that cradle them, are marred with the remnants of rocky beaches, sandy canyons, dusty winds that have been etching away mountains for centuries. But there was no sand, nor rock, nor dust on the surface of Aecor. The frosty spires around us weren’t ice-covered peaks, but simply ice – the purest sea ice, the kind of thing you’d only find in the heart of polar seas back home, far from the grime of shore. Aecor had no shores, no foundation except for that of the ocean floor. We stood upon water, and nothing but.

‘Poor Jack,’ she said.

I laughed. ‘Poor Jack.’ I looked at her. ‘Elena, I’m so—’

She grabbed my arm. ‘Oh, my God.’

Adrenaline shot through me. ‘What?’

‘Turn off your lights.’ I did. She did. ‘Look,’ she said, pointing.

For a moment, there was nothing. My eyes hurried to conform to the darkness, trying to parse the edge between black sky and black ice. But before they could, something else appeared, about a meter ahead of us.

Red. A small patch of soft, fluorescent red, shining quietly up through a hazy pane of ice.

It moved.

I should note that autonomous movement detectable to the human eye is not a conclusive indicator of life. A rock slipping down a hill is not alive. A river is not alive. Lichen, on the other hand, is very much alive, as is pond scum and the yeast in bread dough, but you won’t see any of these pick up and scurry across a room (one would hope). Even so, if you see something wiggle its way forward when nothing else around it is moving, there’s not a scientist in the world that wouldn’t make an assumption there.

Elena remembered protocol before I did. ‘Camera,’ she said.

Her voice snapped me into action. ‘Camera.’ I heard a faint click in my helmet as the onboard recording equipment got to work.

‘There’s a light in the ice ahead of us,’ she said, delivering her words with academic composure. ‘We noticed it a few seconds before we began recording. Not sure how long it’s been there. Flight engineer O’Neill and I are approaching carefully to take a closer look.’

The ice crunched beneath our boots as we walked. My pulse raced as my brain helpfully supplied images of angler fish and glow-worms, luring in the hypnotised to a toothy end. I imagined the ice splintering, the solid surface destroyed as a monstrous alien maw rose up and swallowed us whole and screaming. But Elena walked steady, and so I walked steady, wearing her bravery as my own.

To my relief (and perhaps surprise), there was no splintering, no swallowing. What there was was light – more light, another and another and another. We could tell their sources were bright, and I’m sure if we’d seen them in clear water, their silhouettes would’ve been crisp and precise. But the ice muted the light, blurring its edges, scattering it in hazy auras that shimmered well beyond the source. New colours joined the party – orange, pink – and new shapes as well. There were snake-like things, full-bodied things, worms and flowers and combs. Some shoaled by the dozens. Some travelled alone. Some bobbed. Some chased. The ice sheet below us became a luminescent symphony, and Elena stopped narrating for the camera. I understood why. None of our words in the moment were good enough. Imagine a summer carnival behind a wintered windowpane. Imagine the most fabulous aurora you’ve ever seen, shining below your feet.

Elena and I laughed. I grabbed her hand. She pulled me in, her arm wrapped snugly around my shoulders, the top of my helmet resting against the bottom of hers. We were one being, one moment, all boundary of body and person dissolved in the presence of shared euphoria. We stood like children, pointing and gasping. I forgot why she’d gone out onto the ice. It seemed she had as well.

I heard the faint rush of the airlock behind us, followed by a clatter down the ramp and a burst of running. Chikondi – undoubtedly having seen the feeds of our cameras pop up on the monitor – came barrelling toward us, a man on fire. Jack came out of the airlock a few seconds later, running for a few steps, stopping to fix the boot he’d hastily shoved himself into, then continuing onward.

Chikondi was beside himself. The dance of light was in full force now, and he turned this way and that, crying out wordlessly. He took a deep breath, and shouted in crescendo: ‘Multi . . . cellular . . . ORGANISMS!’ He raised his face to the sky, thrusting his gloved fists in the air like he’d just scored a championship goal.

‘Holy shit.’ Jack laughed. He put his palms on the top of his helmet. ‘Holy shit.’ He looked at me and Elena. ‘Are you still recording?’

‘Yes,’ Elena said. ‘Every word you say.’

‘Oh. Well.’ Jack walked over to her and turned his gaze straight into her camera lens. ‘Holy shit.’

Chikondi wasted no time in training his flock of camera traps on the ice. For ten days, the little machines recorded the glowing soirees taking place in the water below. We did plenty of work in the meantime, harvesting vegetables in the greenhouse, doing routine inspections of the Merian’s systems, studying the orbital imagery the cubesats sent back every day. We began environmental studies as well, at Elena’s lead. She was in her element atop a frozen sea, where there were ice cores to pull and wind speeds to measure and scrapings to melt down on microscope slides. She worked with laser focus, efficient as ever.

She said nothing of Tampico. The rest of us decided not to ask.

We were her lab techs during this time, and happily so. No astronaut is a pure specialist, and no scientist works alone. To survey an ecosystem, you need to have a base understanding of all its factors. A biologist cannot draw conclusions without knowing how the oceans move and what the air is like. A meteorologist cannot study the composition of the atmosphere without knowing what’s breathing into it. And me – I may be the engineer, but not only are my hands as good with a Petri dish as anyone else’s, but it helps me to know what my tools are being used for. I want to know. If each of us retreated into our own private dens of specialisation, we’d be shooting ourselves in the foot. We benefit from knowing what the other is doing – even Jack, who complained every day about the lack of rocks.