Vacuum exposure

Vacuum

An anatomy of death in low pressure

An unprotected body in hard vacuum does not explode, and it does not freeze solid. It boils at the temperature it already is. Death takes a minute or two. The body keeps for millions of years.

Depicts the death of a human being. The images are invented; the physiology is documented.

Scroll to begin descent

PartI

Ebullism

T + 00:00 → 00:10

His blood is still at body temperature, and it has started to boil.

Water boils at body temperature once pressure drops below about 6.3 kilopascals, the threshold the flight surgeon Harry Armstrong identified. Vacuum crosses it in well under a second, and the pressure never has to approach zero. Vapour leaves first from wherever the body is wettest and least enclosed: the mouth and the sinuses, then the surface of the eyes.

Instrument readings for this stage. Ambient: 101.3 kPa falling to 0 kPa. PO₂ arterial: 95 mmHg falling to 12 mmHg. Soft tissue: 0 % vol rising to 14 % vol. Conscious: TRUE.

An astronaut spins in the mouth of an airlock, backlit by hard white light, a turbulent cloud of vapour bursting from his mouth and nose. His face is lost in the glare.The same face, closer: the eyes reddened and glazed, ice gathering along the lashes, vapour streaming from the nose and mouth across the frame.

PartII

Anoxia

T + 00:10 → 00:15

The thrashing stops before the falling does.

The lungs are worse than useless now. At this pressure they empty instead of filling, and a held breath tears them. Consciousness runs on the oxygen already in the blood between the lungs and the brain: nine seconds of it, maybe fifteen. Then it is gone, mid-motion, and the body carries on at exactly the speed it was already travelling.

Instrument readings for this stage. Cerebral O₂: 5 s falling to 0 s. Motor response: ACTIVE changing to NIL. Ambient: 0 kPa. Conscious: TRUE changing to FALSE.

The same astronaut, limp and drifting in a bright white corridor. The vapour has gone. Nothing about his posture is intentional any more.

PartIII

Edema and Frost

T + 00:15 → 01:00

He is not freezing. He is evaporating, and that is what carries the heat away.

Vacuum is an excellent insulator, because there is nothing to conduct heat into. Heat still leaves two ways. He radiates, slowly, for as long as he is warm. He also boils off his own moisture, which is faster, and stops when the water is gone. Frost forms on the outside while the tissue underneath keeps swelling. Unrestrained it would reach roughly twice its normal volume. The suit holds it to less.

Instrument readings for this stage. Soft tissue: 14 % vol rising to 70 % vol. Surface temp: 33 °C falling to -18.4 °C. Core temp: 37 °C falling to 36.9 °C. Sublimation: 0 g/min rising to 2.4 g/min.

A tight view of the suit's collar ring and shoulder, every surface furred with fine white frost. The face above is a shape in deep shadow.

PartIV

Beyond the Infinite

T + YEARS

Nothing out here is coming to take him apart.

Decomposition is work that living things do to a body, and there is nothing alive out here to do it. There is no oxygen either, and no water. The drying finishes itself and then stops, having run out of anything to remove. The body holds its shape and its heading, and on its current course it will still be recognisably a body in a million years.

Years later, in deep space lit only by cold blue starlight: the suit is cracked and faded, drawn tight over a shrunken body. Where the face was there is a dark hollow inside the neck ring.

1 : 4 : 9

He will arrive somewhere eventually, entirely unchanged.

Nothing out here is dense enough to erode him or warm enough to thaw him, and nothing out here is alive. Preservation is not something happening to the body. It is what is left once every process that would undo a body is missing. The suit will outlast the agency that launched it, and probably the language its checklists were written in.

Four stagesEbullism · Anoxia · Edema · DesiccationWebGL 2

The physiology follows published accounts of decompression exposure. On 14 December 1966, a NASA engineer named Jim LeBlanc was testing a prototype lunar suit inside a vacuum chamber at the Manned Spacecraft Center in Houston when the hose pressurising it came loose. His suit fell from 3.8 psi to about 0.1 psi in ten seconds. LeBlanc stayed conscious for roughly fourteen of them, and what he remembered afterwards was the saliva boiling off his tongue. He came out of it with an earache. The images here are speculative reconstructions and depict no real person or incident.

Form and proportion after 2001: A Space Odyssey, directed by Stanley Kubrick and written with Arthur C. Clarke, 1968. The slab at 1 : 4 : 9, the one-point symmetry and the single red eye are all borrowed. This is an homage, unaffiliated with the film or its rights holders.

created by ømerburakpolat