Airlock

Rafael was counting when Imogen recognised his voice. He had reached four, although she couldn't remember him starting, and he was asking her to keep her eyes on the small round window in the inner hatch. ‘Five,’ he said. ‘Good. Tell me where you are.’ She tried to turn towards him. An unpleasant heat travelled from the back of her head into the hinge of her jaw, and she found herself moving sideways in a way that did not correspond to the movement she had intended. Her right boot knocked against the wall. For a moment she was occupied with the simple business of catching a handhold. ‘Imogen?’ Rafael called again, and she managed to bring her face towards the window without letting go of the rail. ‘Airlock. I'm in the airlock.’ Her voice sounded thick to her. ‘Why are you counting?’ ‘Asha's checking you. Stay put for a minute while we finish.’ He had that deliberate calm he used when somebody's tool tether had snapped during an EVA. ‘Where would I go?’ ‘At the moment I'd rather you didn't demonstrate.’ He answered immediately. His face occupied only part of the hatch window. It was a thick pane set inside the circular locking mechanism, and he was leaning close to it, one cheek flattened slightly by the angle. Imogen could make out the collar of his blue station shirt and the dark strip of the communications lead across his shoulder. Behind him, something pale moved and resolved into a hand passing a tablet out of view. She was floating half-lengthwise beside the suit stowage panel, caught between a loop of webbing at her thigh and her own uncertain grip on a yellow rail. Her EVA suit was still on, its upper assembly open at the neck. She had removed her helmet and gloves. The helmet was secured in its rack, exactly where she would have put it after repressurisation; one glove remained tethered to the suit, while the other was attached to a small wall clip near the equipment panel. She had followed that sequence often enough to do it without thinking. The wet feeling beneath her hair drew her hand upwards again. Before her fingers reached it, Asha's voice came through the chamber speaker. ‘Don't touch the back of your head. I've asked you twice, I'm afraid. Which is an irritating thing to hear when you've only just found out you may have injured it.’ Imogen obeyed, but her fingertips were already pink. The swelling above her left ear was tender, and there was a little blood caught in her hair. ‘May have?’ ‘You struck the aft equipment frame. Rafael saw it happen. There's an abrasion and some swelling, and I'd like to establish how well you're orienting yourself.’ Asha paused while an open channel clicked somewhere behind her. ‘Full name, please.’ ‘Imogen Hale.’ She adjusted her grip to stop her arm drifting away from the rail. ‘And where are we?’ ‘Aster station, low Earth orbit. I know there's no prize for getting that right.’ ‘There is, actually. A very poor one, and I'm keeping it for later. Tell me what you were doing before you came inside.’ ‘Replacing the thermal blanket attachment on the external radiator joint, then checking the latch indicators on the aft service panel.’ She could picture the bent lip of the panel and the ridiculous difficulty of getting a gloved fingertip beneath it. ‘Rafael wanted photographs of the witness marks before I closed the cover.’ Asha asked her to carry on from there. Imogen explained that she'd returned to the airlock, and when Asha asked about repressurisation, she answered yes without thinking. She searched for the sound of the pumps and the figures rising on the display. She had an impression of taking her helmet off, folding the communications cap into its bag, but the equipment around her could just as easily have supplied those details. ‘I think so,’ she amended. ‘Don't fill in the blanks for me,’ Asha said, without any reprimand in it. ‘What's the last thing you can actually see in your memory?’ Imogen looked at her hands. The nails were short, with a pale crescent of grime along one thumb where the glove lining had rubbed. In the moment before she had recognised Rafael's voice, she'd been somewhere else. Not dreaming; there had simply been no place at all. She tried to follow that absence backwards. ‘The outer hatch,’ she said eventually. ‘The green telltale. I secured it, checked it and started the cycle. I remember telling Rafael the seal looked good.’ ‘All right,’ Asha said, making a note. ‘What's happened? I know you say I hit my head, but nobody will tell me what happened before that.’ ‘We'd like you to keep reasonably still while we finish checking you. There are other things being reviewed.’ ‘That's a careful way of saying you don't want to answer.’ Rafael moved back into the middle of the window. ‘The injury's the part we can deal with immediately, Imogen. We will explain the rest.’ She studied the hatch instead of his face. The locking indicator beside the manual lever was green, and the differential pressure display showed zero within its normal tolerance. The airlock itself was quiet apart from its circulation fan, the faint ticking sound made by the suit's cooling assembly as it shed heat, and three voices connected to her through the speaker. She was breathing cabin air. The outer hatch was behind her and sealed. The inner hatch was closed despite the pressure on either side being equal. ‘Open up,’ she said, expecting Rafael to reach for the hatch controls. He stayed where he was, one hand hooked beneath the window surround. ‘I'm concussed, Rafael. Get me inside so Asha can examine me properly.’ ‘That's what we're working on.’ He used those words whenever a repair had acquired complications. She waited for him to explain. A separate tone sounded from the communications console, followed by a click as another channel joined the circuit. ‘Aster, Control. Medical, we're receiving Hale's responses on the recorded loop. Commander, confirm the inner hatch remains secured.’ The ground controller's voice was lower than Asha's and slightly flattened by transmission, but the delivery was familiar. Elena Torres, the duty flight director, had a habit of leaving a deliberate space before the point of an instruction. Imogen had privately accused her of building those pauses into the training package. ‘Confirmed,’ Rafael said. He read the pressure differential once more before returning his attention to the window. Elena continued, ‘Maintain the current configuration while the engineering and medical teams complete their assessment.’ ‘Elena, I'm the one in here,’ Imogen said. The other woman had apparently joined the conversation at the exact point when she should have been going to the medical bay. ‘I know, Imogen. I've been listening. How is your head?’ ‘Attached. For now. You can explain the assessment while I keep it that way.’ ‘There was an anomalous event during your post-EVA procedure. We're reviewing the instruments and the crew report.’ Elena let the words stand, plainly aware they amounted to very little of what Imogen wanted to hear. ‘What kind of anomaly? If you've got an equipment fault, I can help from somewhere that has a chair.’ ‘We're still trying to establish what it was,’ Elena said. ‘That's why we'd like the hatch to stay closed for the moment. We're looking at options for a safe medical transfer, and nobody is leaving you without support.’ ‘We don't have a chair, strictly speaking,’ Asha added, sounding faintly put out at the comparison. ‘I could make one out of Velcro.’ In the window Rafael's mouth altered as if he might smile. It passed so quickly she couldn't be certain. Imogen drew herself up against the handhold, testing the movement in small increments. She felt nauseated when she turned her head too quickly. The inside of the chamber was familiar enough that she could account for every panel without looking: communications and atmospheric readouts forward, tools and suit service connections on the right, emergency oxygen regulators beside the scrubber housing, two handrails she had installed herself during the commissioning review. The rubber sleeve around the lower rail had a narrow split from where someone had trapped a tether buckle beneath it three months before. She had spent a disproportionate amount of her life ensuring the airlock could be entered and left safely. Being told to remain there while other people decided what had gone wrong was beginning to irritate her. ‘How long?’ Imogen asked. Elena began to tell her they couldn't yet give a reliable estimate, but Imogen interrupted. ‘Since I came in. How long have I been here?’ Rafael consulted a display out of sight of the window. ‘Twenty-one minutes since outer-hatch closure. Just under fourteen since repress finished.’ Asha gave the duration of their conversation as two minutes and forty seconds. Imogen tried to arrange the figures around what she remembered. She had seen the outer-hatch indicator turn green, started repressurisation and somehow ended up with her helmet in its rack. Nothing joined that sequence to Rafael's counting. A hard metallic clack and a pressure number that seemed wrong surfaced briefly, then dissolved when she tried to examine them. ‘How much have I lost?’ ‘Approximately seven minutes around the impact,’ Asha said. ‘That doesn't mean you were unconscious all that time. You came round relatively quickly, but you were confused afterwards. We're still aligning the recordings.’ ‘And what was I saying?’ ‘Mostly asking what was wrong with the hatch.’ Imogen's eyes went straight to the circular operating wheel beside it. ‘Did something happen to the hatch mechanism?’ she asked. Asha deferred to Rafael, who was already checking the readouts on his side. On the other side of the window, Rafael shifted so that she could see his shoulders and, briefly, more of the hab behind him. The lighting was the same as always. A drink pouch was secured near the rack, its white tube curled neatly beneath a strap. Someone had left an inspection mirror hanging on a temporary hook. ‘The hatch is holding pressure,’ Rafael said. ‘Both seals are healthy and we've verified the locks.’ She considered that for a moment. ‘You've checked the things I would have checked. You haven't told me why you're keeping it closed.’ ‘I know,’ he said, and left it there. Asha returned to her examination. She had Imogen follow a small white tab on her wrist display with her eyes, then lift each hand in turn, push against a restraint and report whether either side of her face felt different. Imogen performed the checks, aware of her impatience but also of the unpleasant uncertainty in her own movements. Her left hand arrived at a handhold slightly later than she expected. Asha instructed her to stop pulling against the suit tether and place both boots in the nearest restraint loops instead. ‘It isn't an emergency exercise,’ Imogen said, fumbling with the second boot. ‘No,’ Asha agreed. ‘If it were, you'd be much more annoying, because you'd have prepared jokes.’ The loops held her securely enough that the chamber stopped turning around her whenever she moved. Her stomach settled. Asha asked about double vision, vomiting and neck pain, and had her check the emergency pressure indicator and the personal environmental panel without bending forward. The panel offered no immediate reason to worry about her breathing. The atmosphere was at one hundred and one kilopascals, oxygen within nominal range and carbon dioxide well below the warning threshold. The circulation fan was maintaining normal flow, and whatever Ground feared, it hadn't made the air unsafe to breathe. Asha advised her to rest her head as much as the stiff suit assembly would allow and to drink a little water, provided she could reach the pouch without twisting. She listed the symptoms she wanted reported immediately, then added, ‘And please don't do anything clever with the equipment yet.’ ‘That last part's a bit unreasonable.’ ‘You can register a complaint when I've finished checking you.’ Imogen was about to ask Rafael to release her when the panel above the scrubber housing made a small mechanical click. A status light changed from SHARED RETURN to LOCAL CIRCULATION. Another light, labelled ISOLATED CO₂ REMOVAL, came on beneath it. The fan pitch altered by an almost imperceptible amount. She recognised the sequence. It was the quarantine configuration used during systems tests, separating the airlock's atmospheric loop from the habitat while keeping the chamber pressurised and powered. It was not a configuration she had ever expected to inhabit while injured. ‘Who authorised that?’ she asked, watching the isolation indicators settle. ‘Ground and I agreed to isolate the shared return until we've identified the hazard,’ Rafael said. ‘The chamber's emergency scrubber is running. Oxygen top-up remains available.’ ‘You've just switched me to a consumable.’ Her thumb moved to the new capacity field, which was still blank while the controller checked the cartridge identifier. ‘Yes. I know what that means.’ ‘Then tell me how much life it's got left.’ ‘We're checking what was loaded after the last maintenance cycle,’ Rafael replied. His face remained in the window while she watched the figures search for a value. She wanted to tell him he should already know. He probably agreed. ‘Please check quickly,’ she said instead. ‘We're doing that now.’ Asha interrupted to ask whether the headache had changed. Imogen told her it hadn't, which was true as far as she could tell. The pain had become a steady, unpleasant pressure behind her left ear. She eased the webbing at her thigh and stayed with her boots in the loops, where she could keep Rafael in view without having to turn her head. For several minutes they completed the tasks involved in caring for an injured crewmember. Asha recorded answers, Rafael located the correct medical checklist, Elena asked for updated atmospheric figures. Imogen drank a little water from the pouch attached to her suit and discovered that the simple act of managing a straw while wearing most of an EVA suit was difficult enough to occupy her whole attention. Nobody raised a voice. Nobody offered an explanation for the closed hatch. When Asha finally gave her a pause, Imogen reached carefully for the nearest wall tablet and turned it so she could read the event log without removing her feet from the restraints. She wasn't supposed to do anything clever with equipment. Looking at a clock hardly qualified. There, below the outer-hatch closure and repressurisation entries, was a run of status messages she could not account for. One line was stamped a fraction before another that should have preceded it. The recorded impact followed them. Seven minutes separated the beginning of the irregular sequence from the first complete, coherent response attributed to her. She read it again, then used a fingertip to enlarge the timestamps. Outside the window, Rafael was still speaking to Ground. Imogen let the conversation continue. She had worked on the chamber's logging system during certification. Its clocks were supposed to agree.