Naked Science Forum

General Science => Question of the Week => Topic started by: Sally Le Page on 05/10/2021 15:50:16

Title: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Sally Le Page on 05/10/2021 15:50:16
This week, listener Daniel asked us:

"If a crew on a mission to Mars has a death on board and the body was released into space, would that body ever decay?"

What do you think? Let us know below!
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Halc on 05/10/2021 16:04:10
Once launched into space (presumably in a non-pressurized coffin), the body will quickly mummify from dessication as any moisture boils away. Lack of moisture means that anaerobic bacteria and other decay agents will not decompose the body.

It takes time to completely dry a body, so some decomposition will occur in the initial hours, but it will drop off sharply over time.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: alancalverd on 05/10/2021 16:29:52
Depends on his last meal, to some extent. Dead foxes, badgers and hedgehogs at the roadside tend to stay pretty much in shape until eaten by  birds and rats, but the abdomen of a dead deer, horse or rabbit inflates very rapidly. So never mind the occasional meteor - watch out for exploding interplanetary vegetarians.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: chiralSPO on 05/10/2021 18:35:16
The desiccated corpse (think beef jerky) would slowly release other less volatile, but still vaporizable compounds for several years, and then would be ablated by ionizing radiation from the sun and solar wind and cosmic rays, and periodically impacted or punctured by mm-sized grit particles whizzing by. It would take a really long time for the flesh to be completely stripped (I would guess it would be on the order of hundreds of thousands of years, but I could be off by an order of magnitude or two).

The skeleton would probably last a good while longer. It would most likely only be destroyed if it actually hit a large object (or fell to a massive object). Otherwise, I feel like it would be no different from other rocky objects in the inner solar system. It could go for billions of years, to eventually be vaporized when the sun goes red giant (unless by that time it has gotten ejected from the solar system, or at least moved farther away.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: evan_au on 06/10/2021 09:17:14
Even without micrometeorite impacts, continual exposure to intense UV and X-Ray radiation, as well as bombardment by solar wind and cosmic rays would gradually break down the organic chemicals in the body.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Liaata on 06/10/2021 16:36:19
You would need bacteria to decompose. Since they do not have water to live, you will not decompose.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Colin2B on 06/10/2021 17:50:03
You would need bacteria to decompose. Since they do not have water to live, you will not decompose.
The human body is around 60% water. Not sure how long it would  take to evaporate, but you could seal it in a body bag.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: fenix21 on 09/11/2021 17:00:45
Hello, for sure, if a body falls somewhere, it will surely fall apart, even if it keeps falling all the time, there is still an atmosphere and there the body will burn for sure and very quickly, unfortunately, any thing you throw somewhere out of space will never fall to the ground in the atmosphere
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Ken Raisen on 22/01/2022 12:52:31
A dead body will definitely decompose in space. Even though there is no bacteria or any micro organisms present in space, a human body carries bacteria. So gut bacteria will eat your body from inside. It takes a long time though.

But before you completely decompose that way, your body has high chances of burning in space by sun or stars or any other ways like falling into an atmospheric region where your speed burns you. The time of decomposition is random though.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Origin on 22/01/2022 13:47:48
A dead body will definitely decompose in space. Even though there is no bacteria or any micro organisms present in space, a human body carries bacteria. So gut bacteria will eat your body from inside. It takes a long time though.
No that won't happen.  Due to the lack of moisture, lack of air and the extremely low temperatures there will be no bacteria alive.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: Ken Raisen on 23/01/2022 05:52:53
A dead body will definitely decompose in space. Even though there is no bacteria or any micro organisms present in space, a human body carries bacteria. So gut bacteria will eat your body from inside. It takes a long time though.
No that won't happen.  Due to the lack of moisture, lack of air and the extremely low temperatures there will be no bacteria alive.

Recent researches shows that bacteria from earth can survive in space for few years if they remain in clusters.

But 'Bacterial growth' is not possible in space i guess. And degradation happens only by bacterial growth. So like you said, human body to decompose that way is not possible.
Title: Re: QotW - 21.10.9 - Would a dead body in space decompose?
Post by: chiralSPO on 24/01/2022 02:12:49
If the body were encased in such a way that the moisture and heat were contained for a while (weeks), I don't see any reason that some amount of bacteria-driven decomposition couldn't happen. (technically, the Earth and everything on it is "in space")

But if the body were unprotected from the vacuum and temperature of space, I don't think that biotic decomposition pathways would be very reasonable...