What happens to the body in space?

Preventing organ damage and boiling blood, spacesuits protect astronauts from the deadly conditions of an icy vacuum

(Image source: Pixabay)

The human body, while perfectly suited to conditions on Earth, wouldn’t fare quite so well when exposed to the conditions in space. To protect it, spacewalkers wear spacesuits. These can maintain comfort for the astronaut in varying extreme temperatures, from around minus 150 degrees to plus 120 degrees Celsius. Additionally they supply oxygen to breathe, water to drink and protection from the impact of tiny particles, bright light and radiation.

So how long could we last in space without these vital outfits? If for some reason you were to find yourself floating unprotected in space, the experience would be a brief one. You would remain conscious only for a matter of seconds before passing out and dying a few minutes later from oxygen deprivation.

Without air to breathe in the void of space, our instincts might tell us to hold our breath in this situation – but this would be a mistake. The low pressure created in the vacuum would cause any oxygen held to drastically expand, rupturing internal organs.

While spacesuits are life-saving, travelling into space can still have a huge impact on the body, even with this protection. Those enclosed in space stations are subjected to ten times the radiation experienced naturally on Earth. Astronauts who venture into orbit understand the strains they put their body under. Their specific regimes help to keep this impact on their body to a minimum, exercising daily to keep muscles strong and bone deterioration at bay.

Exposing the body to space

(Image credit: Future PLC)

Instant vaporising

Any liquid exposed on the body will instantly begin to vaporise. Wet surfaces such as the tongue and eyes will start to boil.

15 seconds- Loss of consciousness

You could endure only 15 seconds of outer-space conditions before losing consciousness. This is due to oxygen in the blood rapidly diminishing.

90 seconds- Death by asphyxiation

Around 90 seconds into space exposure, you would die. All oxygen is used up and the body can no longer be sustained.

12 hours- Hot or cold

In some areas of space, extreme temperatures plummet far below zero, while near the Sun temperatures soar. Between 12 and 26 hours the entire body would either be frozen or burnt to a crisp.

Beginning to bubble

19,202 metres or higher above Earth in outer space, extremely low atmospheric pressure causes body fluids to bubble within the tissues.

Extreme expanding

Human flesh would expand to twice its size in a ballooning effect, but your elastic skin will still hold you together.

Changing colour

As oxygen leaves the blood, skin colour is altered. The body would adopt a pale-blue tinge. After one minute circulation would stop altogether.


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