# Blood clotting in Outer Space

**URL:** <https://boards.straightdope.com/t/blood-clotting-in-outer-space/714398>\
**Category:** Factual Questions\
**Created:** [March 6, 2015, 11:44pm UTC](https://boards.straightdope.com/t/blood-clotting-in-outer-space/714398 "2015-03-06T23:44:24Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Doctor\_Why\_Bother](https://avatars.discourse-cdn.com/v4/letter/d/e19adc/32.png) [@Doctor\_Why\_Bother](https://boards.straightdope.com/u/Doctor_Why_Bother)\
**Post date:** [March 6, 2015, 11:44pm UTC](https://boards.straightdope.com/t/blood-clotting-in-outer-space/714398/1 "2015-03-06T23:44:24Z")

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Hi all, I’m writing a little sci-fi story and need help on a plot point. Without going into the gory details, I need to know if zero gravity has any effect on blood clotting. Like, if someone cuts themselves in space will the cut stop bleeding more quickly than on Earth or more slowly or will it not make any difference? I’ve tried googling about and haven’t found anything. Cites would be appreciated as I’m trying to make the story as realistic as possible so it would help with my research. Cheers.

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**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\
**Post date:** [March 7, 2015, 12:36am UTC](https://boards.straightdope.com/t/blood-clotting-in-outer-space/714398/2 "2015-03-07T00:36:55Z")

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Did you see this while you were searching?

> [@](#):
>
> Astronauts have to be very careful when they’re in space, explains Harry Whelan, a neurologist at the Medical College of Wisconsin in Milwaukee. “Minor injuries typically don’t heal until they land,” he says. The reason for this is not well understood, but a cell’s mitochondria–its energy sources–don’t function as efficiently in zero gravity, and this leads to a variety of health risks.

From here:  
Clotting Blood In Zero-G

> **[Clotting Blood In Zero-G](https://www.spacedaily.com/news/microgravity-99i.html)**
>
> Washington - September 23, 1999 - Even a small nick won't heal properly in zero gravity--a problem that has made astronauts' jobs just that much tougher. Now NASA is learning how to heal wounds with light.

This article doesn’t deal so much with the clotting, but does deal with a lot of other practical aspects of injuries in space:

> **[Blood in Zero Gravity: NASA Tries to Prepare for Surgery in Space](https://www.theatlantic.com/technology/archive/2012/10/blood-in-zero-gravity-nasa-tries-to-prepare-for-surgery-in-space/263171/)**
>
> Zero gravity and bodily fluids are a dangerous combination.

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<div class="post-metadata">

**Author:** ![Doctor\_Why\_Bother](https://avatars.discourse-cdn.com/v4/letter/d/e19adc/32.png) [@Doctor\_Why\_Bother](https://boards.straightdope.com/u/Doctor_Why_Bother)\
**Post date:** [March 15, 2015, 12:23pm UTC](https://boards.straightdope.com/t/blood-clotting-in-outer-space/714398/3 "2015-03-15T12:23:21Z")

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Completely forgot I started this thread! Thanks engineer! Those links were really useful 🙂