8
$\begingroup$

DISCLAIMER: No, this is not a duplicate of this question. We are talking about reentering Venus' atmosphere as opposed to Earth, and the suit parameters are rather different to a current suit.

Background:

A terrorist has detonated a bomb on the main character's ship, in low equatorial orbit ~200 km above Venus. They are on a hull inspection EVA at the time, and to escape the blast hide behind one of the many auxiliary craft on the ship, a biological sample pod designed to evaluate habitability of Venus' atmosphere. Unfortunately, the explosion triggers the automatic debris avoidance program and activates the pod's engine in such a way that the character and biopod are now on an atmospheric entry trajectory.

The suit is made with carbon nanotube fabric in most places, except where impossible. There, they use standard MMU-like materials. The suit has a delta-v comparable to SAFER, an oxygen reserve of 8 hours and a parachute to be used in emergency deorbit situations. Mass is 70 kilograms.

The biopod is not designed to survive surface conditions on Venus, its purpose being to float in the atmosphere at an altitude of 30-50 km to test survivability of microorganisms in this environment.

Can they survive this situation(i.e land on Venus or return to ship successfully, with survivability for the nominal EVA duration)? If not, what is needed to allow it?

I appreciate your feedback. Thank you!

$\endgroup$
11
  • $\begingroup$ Is this auxiliary craft capable of landing? $\endgroup$
    – Alexander
    Commented Aug 5, 2020 at 16:21
  • $\begingroup$ @Alexander No, it is designed to float in the atmosphere at an altitude of ~30-50km. $\endgroup$
    – Lelu
    Commented Aug 5, 2020 at 16:48
  • 2
    $\begingroup$ Aha, so it's never has to be exposed to the pressure and temperature at the surface level. I think you should mention that in the question. $\endgroup$
    – Alexander
    Commented Aug 5, 2020 at 16:50
  • $\begingroup$ Ok, this is not exactly what I had in mind. Does the pod (or the suit, by any chance) has any landing (or upper atmosphere gliding) capabilities (engines, parachutes etc.)? Without those, it will be certainly doomed. $\endgroup$
    – Alexander
    Commented Aug 5, 2020 at 17:05
  • $\begingroup$ @Alexander The pod has propulsion systems that are designed to keep it stable and relaunch from Venus atmosphere, but no landing gear or parachutes. The suit has a parachute in case of emergency. $\endgroup$
    – Lelu
    Commented Aug 5, 2020 at 17:07

2 Answers 2

19
$\begingroup$

No, you would burn up in the atmosphere of Venus. The Safer unit can supply an orbital delta V of perhaps 3 m/s, whilst orbital speed around Venus will be very roughly 8000 m/s so it won't make any difference. The parachute would not work at orbital speeds, it would be shredded and burnt. Even with sufficient braking the atmosphere is so dense and hot that you would die long before reaching the ground.

Further to editing of the original question: Plan B suggestion - use a heat shield to shed most of the orbital speed then jettison it and use a ballute inflated with oxygen/nitrogen to slow further still. Very tricky but if you do it right and use a few atm pressure to inflate the ballute you could end up floating in the atmosphere of Venus high up where the temperature is around 20 degrees C. Then climb into the ballute and await rescue. Not good but much better than trying to land.

$\endgroup$
11
  • 12
    $\begingroup$ Also it rains sulfuric acid. $\endgroup$
    – Halfthawed
    Commented Aug 5, 2020 at 16:39
  • 2
    $\begingroup$ You will need a very strong protective capsule capable of withstanding a pressure of 93 atmospheres. This is the pressure at around a kilometre down in Earth’s oceans. It must also resist a temperature of 465 degrees C whilst keeping the contents at less than 30-40 degrees C, so will need some very fancy cooling arrangements. Some form of ballute might be used but a heat shield would also be needed ( especially in very of the surface temperature). $\endgroup$
    – Slarty
    Commented Aug 5, 2020 at 17:06
  • 1
    $\begingroup$ Plan B suggestion - use a heat shield to shed most of the orbital speed then jetison it and use a ballute inflated with oxygen/nitrogen to slow further still. Very tricky but if you do it right and use around 1 atm pressure to inflate the ballute you could end up floating in the atmosphere of Venus high up where the temperature is around 20 degrees C. Then climb into the ballute and await rescue. Not good but much better than trying to land. $\endgroup$
    – Slarty
    Commented Aug 5, 2020 at 17:13
  • 2
    $\begingroup$ Venice is a terrible place.. $\endgroup$ Commented Aug 6, 2020 at 2:21
  • 5
    $\begingroup$ @Greg Burghardt - Venice? $\endgroup$
    – Slarty
    Commented Aug 6, 2020 at 9:02
15
$\begingroup$

Get in the biopod

The biopod is activated and it is going thru its programmed routine. The biopod does not land on the surface. The biopod does not burn up in the atmosphere. It descends from orbit to float at described height, gathers samples and then returns.

Your character might burn up on the outside of the biopod as it sheds velocity and descends to its sample gathering height. If he can get in there he will be protected. It is biopod as escape pod.

$\endgroup$
5
  • 3
    $\begingroup$ This sure will go down as "that time we found life on Venus" incident in space exploration. $\endgroup$ Commented Aug 6, 2020 at 4:23
  • $\begingroup$ "[the biopod']s purpose being to float in the atmosphere at an altitude of 30-50 km" it's unclear to me whether OP means that the biopod has a means of simply stopping at that altitude to avoid damage, or if that's just what it's designed to withstand and will simply precipitate to the surface of the planet uncontrollably if there isn't an external force keeping it at the right altitude $\endgroup$ Commented Aug 6, 2020 at 7:21
  • $\begingroup$ Nevermind, it was addressed in the comments. Your answer is definitely solid $\endgroup$ Commented Aug 6, 2020 at 7:23
  • $\begingroup$ However the buoyancy of the Biopod will be reduced by the extraweight of the body... Both will end up a little lower in Orbit then planed... $\endgroup$
    – T-Me
    Commented Aug 6, 2020 at 10:34
  • $\begingroup$ @T-Me - I bet the biopod has ballast on board. Like a balloon or ship that has a desired buoyancy it can jettison the ballast as it takes on samples. That would be good for the fiction - manually clearing out the ballast to make room. $\endgroup$
    – Willk
    Commented Aug 6, 2020 at 12:42

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .