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As the question says. Could a human in an appropriate space suit survive the forces, temperatures etc they would experience during the atmospheric entry, parachute descent and skycrane landing as used by Curiosity and Perseverance to land on the surface of Mars?

(Lets assume it sets them down within walking distance of a nice new pre built Mars base...)

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    $\begingroup$ Temperature inside the MSL aeroshell remained room temperature, even though the external surface of the heatshield reached around 1,300°C. I don't know how the temperature profile changed once the heatshield was ejected, but it happened at <600 km/h (Felix Baumgartner withstood this) and I expect things would get cold pretty quickly thereafter. So I don't think temperature would be a problem. It's likely just the G forces that cause the biggest problem - which are well into the "uncomfortable" range. $\endgroup$
    – Wyck
    Aug 23 at 18:26
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    $\begingroup$ Did you just watch an episode of "For All Mankind"? $\endgroup$
    – Barmar
    Aug 25 at 14:26

2 Answers 2

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Probably not without injury. The deceleration level was too high for crew who would have been in free fall for months.

Additionally, the months-long transit from Earth will mean that deceleration limits must be in place to protect the deconditioned crew. While robotic missions with parachutes can have peak entry decelerations exceeding ten Earth g’s, the generalized maximum requirement assumed for Mars human scale EDL missions is four Earth g’s.

Reference: ENTRY, DESCENT, AND LANDING GUIDANCE AND CONTROL APPROACHES TO SATISFY MARS HUMAN MISSION LANDING CRITERIA

Here is the actual entry acceleration from MSL

enter image description here

Reference: Mars Entry Atmospheric Data System Trajectory Reconstruction Algorithms and Flight Results

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    $\begingroup$ Note that the skycrane's not the problem -- that looks like it hits maybe 1 g max. The problem is the aerobraking, which tops out somewhere around 13 gs. $\endgroup$
    – Mark
    Aug 23 at 21:21
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    $\begingroup$ @Mark the question specifically asks about "the atmospheric entry, parachute descent and skycrane landing" What point are you making? $\endgroup$ Aug 23 at 21:35
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    $\begingroup$ @OrganicMarble: Probably that readers of the answer would be interested to know what phase of "entry, descent, and landing" is the most severe. For this datapoint of 1 reader, he's correct. $\endgroup$
    – Ben Voigt
    Aug 25 at 22:11
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    $\begingroup$ Of course you'd read the question body before answering, but the people reading your answer might just scroll down to the answers. Especially if they got here from HNQ and were just idly curious. I think Mark's comment was useful / interesting; maybe the question title vs. body point isn't the best justification for it. Not taking away anything from your answer, although I like that Woody's answer breaks down which part of the graph is which phase of flight. For folks casually interested in space stuff, it's a handy reminder of the mission profile. $\endgroup$ Aug 26 at 3:03
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    $\begingroup$ There is enough info in the Q to figure it out from the graph, so again I'm not saying your answer is incomplete, just that some of the extra things that could be said are interesting, too. I upvoted this answer for showing the full graph; in Woody's answer I was initially just seeing the bold numbers on the left after a claim it was a graph of Gs, and without a separate label I was missing that those were m/s^2. Also this has the parachute-opening jerk. $\endgroup$ Aug 26 at 3:06
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The graph provided in Organic Marble’s answer indicates a maximum deceleration of 13G (plus a nasty jerk, likely when the parachute opened). Below is an excerpt from it, scaled to seconds and G's

enter image description here

Your question did not indicate the physical condition of the crew at re-entry. The following information is based on crew with good physical conditioning and G-force training (astronaut candidates, fighter pilots and race car drivers). After a lengthy microgravity voyage, de-conditioned astronauts would likely be unable to muster the muscle tension used to voluntarily counter G-forces, and would be out of practice doing so. This would certainly affect their functionality during deceleration, but would have an unknown effect on survivability.

The answer to your question depends on your definition of “survive”.

If you mean “a statistical chance they would be alive, but possibly with longstanding deficits from injuries”, the answer is YES. Paul Stapp famously survived multiple rides in rocket sleds, up to 46G https://en.wikipedia.org/wiki/John_Stapp#Work_on_effects_of_deceleration. He sustained multiple injuries during his runs, including bone fractures and retinal bleeds. Kenny Brack survived 214G in an IndyCar crash but spent 18 months in recovery. https://en.wikipedia.org/wiki/Kenny_Br%C3%A4ck#Retirement

If you mean “is the deceleration within NASA’s limit for emergency aborts”, the answer is still “yes”.

If you mean “is the deceleration within NASA’s limit for launch”, the answer is “yes”

If you mean “is the deceleration within NASA’s limit for re-entry”, the answer is “likely not.”

The graph below has a red dot added to show the estimated G's and duration from the graph referenced above.

enter image description here

https://standards.nasa.gov/documents/viewdoc/3315785/3315785

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    $\begingroup$ I don't know whether it's within the bounds of the question, and I don't think it warrants a full answer, but I think this result clearly indicates that it would be possible (if not cheap or easy) to make a descent with a similar method that is suitable for astronauts. $\endgroup$
    – Turksarama
    Aug 23 at 22:51
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    $\begingroup$ The last link is dead. (And why is this graph labeled "Eyeballs In"? Is this showing some kind of limit before your eyeballs pop out? Or is it "ln" for natural logarithm, representing some kind of eyeball-related data on a logarithmic scale?) $\endgroup$ Aug 24 at 8:28
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    $\begingroup$ @user2357112 The amount of g-force the human body can withstand depends greatly on direction. We can survive best if our "eyeballs are pushed inward" :) $\endgroup$
    – Mr47
    Aug 24 at 9:08
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    $\begingroup$ @Mr47, also g's dorso-ventrally (back to front axis) are less likely to cause circulatory issues than rostro caudal (head to butt axis) $\endgroup$ Aug 24 at 23:29
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    $\begingroup$ This also explains the typical seat positions during a rocket launch. $\endgroup$
    – MSalters
    Aug 26 at 10:18

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